Class 9 Biology - Tissues

State the different types of neurons. Explain their functions.

There are three types of neurons.
$$(i)$$Sensory neurons conduct nervous impulses from sense organs to the brain and spinal cord.
$$(ii)$$Motor neurons carry impulses from brain and spinal cord to the muscles and glands.
$$(iii)$$ Associate neurons perform integrative functions of the nervous system.

A tendon connects a .......... to a ..........

Explanation:

Tendons are fibrous connective tissues that connect skeletal muscles to bones.
Tendons are involved in limb movements and prevent muscle injury during strenuous work.

Differenciate between striated and unstriated muscles on the basis of their function and location in the body. Also compare their structure.

Striated muscles are voluntary muscles. Muscles that we can move when we want them to are voluntary muscles. These muscles are mostly attached to the bones and help in body movement. So it is also known as skeletal muscles. For example, Muscles present in our limbs are striated muscles.

Structure: The cells of these tissues are long, cylindrical, unbranched and multinucleate.

Unstriated muscles are involuntary muscles. The movement of food in the alimentary canal or the contraction and relaxation of blood vessels are involuntary movements. It is also known as smooth muscles. For example, Muscles that are found in the iris of the eye, in ureters and in the bronchi of the lungs.

Structure: The cells are long with pointed ends (spindle-shaped) and uninucleate.

Human cheek cells stained and mounted in glycerine were observed with the help of a compound microscope. Name the stain used and name the components of the cell which would be seen:

Human cheek cells stained and mounted in glycerine were observed with the help of a compound microscope. The stain that could be used is Methylene blue. Methylene blue stains negatively charged molecules in the cell, including DNA and RNA.

The components of the cell which would be seen are the nucleus, plasma membrane, and cytoplasm.

Choose the ODD one out from the following terms given and name the CATEGORY to which the others belong.
Example: Nose, Tongue, Arm, Eye
Answer: Odd Term- Arm, Category- Sense organs
Dendrites, Medullary Sheath, Axon, Spinal cord.

Odd Term- Spinal cord, Category- parts of neuron (nerve cell)

The basic structural unit of the nervous system is ...........................

Neuron- The basic structural and functional unit of the nervous system.

Name the location of Nissl's granules

A neuron is composed of three major parts:

1. Cell body

2. Dendrites

3. Axon

Nissl's granules are present in the cytoplasm of the cell body of the neurons along with other cell organelles like Golgi apparatus, endoplasmic reticulum, mitochondria, nucleus, etc. These granules give a slight coloured appearance to the cytoplasm of the cell body. They help in protein synthesis in the neurons.

Name the site of exchange of material between the blood and the surrounding cells.

The site of exchange of materials between blood and the surrounding cells is capillaries. Blood capillaries are the smallest vessels and are only one cell thick. Hence, exchange of materials can easily occur by diffusion across the membranes of blood capillaries.
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Short Answer
Why are white blood cells called the soldiers of body ?

WBC are called the soldiers of our body because they protect our body from disease -causing micro-organisms like bacteria, virus, fungi and protozoa.

Unscramble the jumbled word.
Isecsum

Isecsum unscrambles as Muscles

What is the function of Lymphocytes?

Lymphocytes are of 2 types -T and B lymphocytes which play an important role in cell mediated and humoral immune response respectively.

Name one place where the following tissue is located:
Squamous epithelium

Found in lining the nasal and mouth cavities and lining of blood vessels

Answer the following:
Name the major site where RBCs are formed.

In adults, RBCs are produced in bone marrow. In embryos, RBCs are made in liver.

The longest cell in animals.

The longest cell in animals is the nerve cell.

Mention the components of the transport system in highly organized plants. State the functions of these components.

Xylem and phloem are the 2 main components of the plant's transport system. Xylem helps in the upward transport of water whereas phloem helps in the transport of food from the leaves to other plant parts.

What is visceral muscle? Where is it found?

The muscles which are found in the lining of visceral organs are called visceral muscles. Ex:- Wall of alimentary canal, urinogenital duct etc.

Why do we consider blood as a connective tissue?

Connective tissues have cells scattered throughout an extracellular matrix. They connect different body systems. Blood is considered as a type of connective tissue because it connects the body systems, transports oxygen and nutrients to all the parts of the body, and removes the waste products. Blood has an extra-cellular matrix called plasma, with red blood cells, white blood cells, and platelets floating in it.

What is the role of epidermis in plants?

Explanation for the answer.

1. It provides a protective barrier against pathogens.

2. It has a thick waxy layer coated around it, that prevents water loss.

3. Prevents or reduces water loss and provide protection against mechanical injury and invasion of parasitic

Differentiate between striated, unstriated and cardiac muscles on the basis of their structure and site/location in the body.

	Striated muscles	Unstriated muscles	Cardiac muscles
Structure	Also known as skeletal muscles, they are striated, tubular, multinucleated, branched and cylindrical fibres.	Also known as smooth muscles, they are non-striated, spindle-shaped, uninucleated fibres.	Cardiac muscles are striated, cylindrical, uninucleated, branched fibres.
Location	They are found attached to the skeleton.	They are found in the walls of internal organs.	They are found in walls of the heart.

Diagrammatically show the difference between the three types of muscle fibres.

Three types of muscle fibres are smooth muscle (non-striated), cardiac muscles and skeletal muscles (striated muscles).

What is the specific function of the cardiac muscle?

Explanation-

The uninucleated, striated, tubular, and branched muscles that form the wall of the heart are known as cardiac muscles. They serve to bring about rhythmic contraction and relaxation of the heart to allow the pumping of blood to all parts of the body. The blood is involved in the supply of nutrients and the removal of waste from various organs and tissues.

What are the functions of areolar tissue?

Explanation:

Areolar tissue is made of cells embedded in a large quantity of extracellular matrix (fibres and ground substance). It includes protein fibres such as collagen, elastin, reticulate and ground substances like water and organic molecules.

Functions of areolar tissue:

The areolar tissue help to hold the organs in place and act as packaging tissue.
The layer of skin or the epithelial tissue is connected with the other tissues like blood vessels with the help of these tissues.

Name the following:
(a) Primary functional unit of brin:
(b) The small gap between the consecutive neurons:
(c) Part of the brain that coordinates the voluntary functions:

(a) The brain and the rest of the nervous system are composed of many different types of cells, but the primary functional unit is a cell called the neuron.
(b) The small gap between the consecutive neurons is called a synapse (or synaptic gap, or synaptic cleft).
(c) The cerebellum - part of the brain coordinates voluntary movements such as posture, balance, coordination and speech, resulting in smooth and balanced muscular activity.

Name the following :
(i) The cell body of a nerve cell.
(ii) The waxy layer on the epidermis of the leaf meant to reduce transpiration.
(iii) A non-biodegradable pesticide.
(iv) The physical expression of genes in an individual.
(v) Knot-like mass of blood capillaries inside the bowman's capsule.

i) Cyton

ii) Cuticle

iii) DDT

iv) Phenotype

v) Glomerulus

Answer the following questions.
i) Draw a well labelled diagram of a neuron and name the following parts.
1) Node of Ranvier
2) Nissil granules
3) Cyton
ii) Name the part of the human brain which is concerned with the following.
Seat of memory
Coordinates muscular activity
iii. Mention any three major activities of the WHO.

(i) Refer the given image.

ii) 1. Seat of memory : cerebrum
2. Co-ordinates muscular activity: cerebellum
iii) The three major activities of WHO are as follows
1. Set pharmaceutical standards
2. Suggests Quarantine measures
3. Finances research on various diseases.

Give an account on cellular components of blood.

There are three types of blood cells or corpuscles.

(i) Red Blood Corpuscles (RBC or Erthrocytes): These are circular, biconcave and non-nucleated cells. Their main component is a red-pigmented protein, haemoglobin. The haemoglobin transports O$$_2$$. They are manufactured in the marrow of bones. They disintegrate in the spleen and liver.

(ii) White Blood Corpuscules (WBC or Leucocytes): They are nucleated cells exhibiting amoeboid movement. They protect the body against invading micro-organisms. There are five types of leucocytes.

(a) Neutrophils: These are the most common type of leucocytes (60-70%) in the blood. Their nuclei can occur in more than one form. Hence they are called polymorphonuclear neutrophils (PMN).

(b) Eosinophils (0.5-3.0%): They are motile cells that leave the circulation to enter the tissues during an inflammatory reaction. During allergy reaction, their number increases.

(c) Basophils(0.1%): They play a role in the allergic and inflammatory reaction. They contain heparin which inhibits blood clotting.

(d) Lymphocytes (20-30%): These are smallest leucocytes. They are more common in lymphatic tissues namely the lymph nodes, spleen tonsils and thymus. Lymphocytes called B-cells can produce proteins called antibodies that can get attached to the bacteria and destroy them. T-cells protect us against viruses by attacking and destroying cells in which viruses are reproducing.

(e) Monocytes (1-4%): These are largest leucocytes. They destroy bacteria, dead cells and cell fragments. During chronic infection, their number increases.

(iii) Blood platelets or Thrombocytes: These are minute fragments of cells that play a very important role in coagulation of blood. Their life expectancy is 5-9 days.

Draw a labelled diagram of the T.S. of bone

Human compact bone is composed of parallel columns made up of concentric bony layers called lamellae organized around channels containing blood vessels, lymph vessels and nerves.

Explain the structure and function of neuron.

The structure of neuron: Nerve cells or neurons are the structural and functional units of the nervous system. It consists of three major parts namely, cell body, dendrites, axon.
Cell Body: It is irregular in shape or polyhedral. It contains cytoplasm and certain granular bodies called Nissl's granules which contain a group of ribosomes for protein synthesis.
Dendrites: Dendrites are short fibres which branch repeatedly and protrude out of the cell body. They transmit electrical impulse towards the cyton.
Axon: They are long fibres arising from the cell body with a branched distal end. It terminates in a synaptic knob. It is filled with neurotransmitters.
Parts of axon:
a. Axoplasm: It is the cytoplasm of an axon.
b. Myelin sheath: It is made up of many layers of Schwann cells.
c. Neurilemma: The outermost layer of Schwann cells.
d. Nodes of Ranvier: These are gaps left by a myelin sheath.

Function: The neurons are responsible for the conduction and transmission of the nerve impulses. The stimulus is received and carried by the sensory neurons, analysed and detected by the CNS. The response is given with the help of the motor neurons.

Explain the structure of neuron.

The structure of neuron: Nerve cells or neurons are the structural and functional units of the nervous system. It consists of three major parts namely, cell body, dendrites, axon.
Cell Body: It is irregular in shape or polyhedral. It contains cytoplasm and certain granular bodies called Nissl's granules which contain a group of ribosomes for protein synthesis.
Dendrites: Dendrites are short fibers that branch repeatedly and protrude out of the cell body. They transmit electrical impulse towards the cyton.
Axon: They are long fibers arising from the cell body with a branched distal end. It terminates in a synaptic knob. It is filled with neurotransmitters.
Parts of axon:

a. Axoplasm: It is the cytoplasm of an axon.
b. Myelin sheath: It is made up of many layers of Schwann cells.
c. Neurilemma: The outermost layer of Schwann cells.
d. Nodes of Ranvier: These are gaps left by a myelin sheath.

Draw the diagram of neuron and label any two parts.

The image represents the structure of the neuron and the parts are labelled.

State two functions of areolar tissue.

Functions of areolar tissue:

The areolar tissue help to hold the organs in the place and act as a packaging tissue.
The layer of skin or the epithelial tissue is connected with the other tissues like blood vessels with the help of these tissues.
Repair of damaged tissues

Find the odd one and also write down the common features of others.
(a) Dendrite, Cell body, Axon, Nephron
(b) Epilepsy, Parkinson's disease, Mumps, Alzheimer's disease
(c) Melatonin, Insulin, Glucagon, Ethylene

a) Odd one is the nephron.

A nephron is the structural and functional unit of the kidney. Others are parts of a neuron.

b) Odd one is mumps.

Mumps is a disease in which salivary glands are swollen. Others mentioned in the groups are diseases related to the brain/nervous system.

c) Odd one is ethylene.

It is a plant hormone. The others mentioned are hormones present in animals.

Create a poster/flowchart to depict all that you have learnt in this chapter about plant tissues.

Image result for Create a poster to depict all that you have learnt in this chapter about plant tissues.

What are the two main types of nerves? Write their functions.

The main two types of nerves are sensory nerves and motor nerves.

i) Sensory nerves are also called afferent nerves. They have long dendrites and a short axon. Their function is to carry information from sense organs to the central nervous system.

ii) Motor nerves are also called efferent nerves. They have short dendrite and long axons. Their function is to carry the information from the central nervous system to effector organs (muscles or glands).

Fill in the blank
RBC: Carrier of oxygen; WBC: ...............

Hemoglobin (Hb or Hgb ) is an iron-containing protein present in erythrocytes or Red blood cells (RBC) of almost all vertebrates. Each hemoglobin can bind to four oxygen molecules. It carries oxygen from lungs to tissues. Hence RBC: carries oxygen.

Leucocytes are also called White blood cells (WBC). These are colourless because they lack haemoglobin. WBC is an important part of the immune system. These cells help in fighting infections by attacking bacteria, viruses and other pathogens that invade the body.

RBC: Carrier of oxygen; WBC: Defence mechanism

Which blood cells are without nuclei? What is the advantage of this condition?

The blood cells without nuclei are erythrocytes or Red blood cells. When the RBCs are developing in the red bone marrow, they do have nuclei. However, these nuclei are ejected from the cells when they enter the bloodstream in a process known as enucleation. The advantage for this condition is the nucleus takes up a lot of space in a cell. This space can be used to fit in more hemoglobin. Hence, to carry oxygen more efficiently, RBCs don't have a nucleus.

Write a note on erythrocytes.

Erythrocytes are also called Red Blood Cells. They are biconcave in shape flattened and depressed in the center. They contain a protein called hemoglobin that is responsible for the red color of blood. They are produced in the bone marrow through a process called erythropoiesis. They are then released into the bloodstream. They are oxygen carriers and hence are enucleated. They have antigens present on their surface such A and B. These antigens are responsible for the presence of ABO blood group.

What do you mean by fractured bone?

A complete or partial break in a bone is called a bone fracture. A fracture is caused by high force impact or stress, injury and disease that weakens the bone.

Why are fractured bones plastered?

Fractured bones are bones that are completely or partially broken. To keep these broken bones at their right position, a plaster is used. Casts or plasters are used to help rest a bone or joint and to relieve pain that is caused by moving it. It also helps the fractured bone to grow and join properly.

What makes the blood look red?

Blood is red because of the hemoglobin inside our red blood cells.
Hemoglobin is a protein that forms a complex with iron molecules and together they transport oxygen molecules throughout the body. Iron has the property of reflecting red light and because there is so much iron in our blood, blood looks red.
Hence Haemoglobin makes the blood look red.

What is cavity in bones?

The hollow region inside the bone is called the medullary cavity and is filled with yellow marrow.

Describe the structure of the multipolar neuron.

Neurons are specialized cells that transmit electrical signals in the brain; they are the functional unit of the nervous system.
The primary components of the neuron are the soma (cell body), the axon (a long slender projection that conducts electrical impulses away from the cell body), dendrites (tree-like structures that receive messages from other neurons), and synapses (specialized junctions between neurons).
In some neurons, the axon may be surrounded by an insulating layer known as myelin sheath produced by the surrounding Schwann cells.
Multipolar neurons are neurons that possess an axon and 3 or more dendrites.

Neurons are packed around with some cells. What are these cells called?

Neurons are packed around with cells like neuroglia or Glia cells. It is the non-neural cells that protect the neurons in CNS and PNS. It also helps to maintain homeostasis.

Differentiate between :
Myelinated and non-myelinated axons

The nerves that are insulated by a sheath or myelin are called myelinated nerve fibres whereas the nerves which lack such sheath are called non-myelinated nerve fibres. Nodes of Ranvier are microscopic gaps found within myelinated axons. Their function is to speed up propagation of Action potentials along the axon via saltatory conduction and it is absent in non-myelinated axons. Collateral branches of the nerve fibre arise at the nodes of Ranvier which is absent in non-myelinated axons. In a myelinated nerve fibre, the action potential is conducted from one node to another whereas in an non-myelinated nerve fibre, the action potential is not conducted from node to node. It is carried along the whole length of the nerve fibre. If the axon is covered with myelin sheath, the nerve impulse is faster and in the unmyelinated nerve fibre impulse rate is slow.

Differentiate between :
Dendrites and axons.

Dendrites receive electrochemical impulses from other neurons, and carry them inwards and towards the cell body, while axons carry the impulses away from the cell body. Dendrites are short and heavily branched in appearance, while axons are much longer. Usually, dendrites receive neuron signals, and axons transmit them. Most neurons have a lot of dendrites and only have one axon.

Name the components of the formed elements in the blood and mention one major function of each of them ?

Blood is a fluid connective tissue.It is composed of plasma(55%) and formed elements/blood corpuscles(45%).

There are three types of formed elements(blood corpuscles):

1) Erythrocytes (red cells)

2) Leukocytes (white cells)

3) Platelets (thrombocytes)

Erythrocytes (RBC) - Most abundant type of blood cells. Their main function is transport of respiratory gases,mainly oxygen, but they also carry some carbon dioxide.

They also maintain the viscosity and pH of blood.

Leukocytes (WBC) - These cells have an important function in defence and immunity. They detect foreign or abnormal (antigenic) material and destroy it, through a range of defence mechanisms.

There are two main types:

Granulocytes (polymorphonuclear leukocytes)- neutrophils, eosinophils and basophils

Agranulocytes - monocytes and lymphocytes

Platelets (Thrombocytes) - These are very small discs, 2-4 micrometer in diameter. They are responsible for coagulation or clotting of blood.

Draw a labelled diagram of a neuron with a myelin sheath.

Given appropriate biological/ technical terms for the following:
Cellular components of blood containing haemoglobin.

Erythrocytes or red blood cells (RBCs) are cellular components of blood that contains haemoglobin.

Write one word for each of the following :
(a) A group of similar cells that perform specific function.
(b) Least specialized cells in plants
(c) Cells responsible for increase in diameter of the stem and root of dicot plants.

a)tissue

b)parenchyma

c)Meristamatic cells

Name the three kinds of muscles in the human body giving one example of each.

Human body has skeletal, smooth and cardiac muscles. Skeletal muscles are voluntary and striated. Example: Biceps brachii. Smooth muscles are involuntary and smooth. Example: Sphincters. Cardiac muscle is involuntary and striated. It is present in the heart wall.

Can you consider a cluster of eggs as a tissue? Why?

A tissue is a group of cells having a common origin and performing a common function. A cluster of eggs is not a tissue since each egg has individual function and they don't function as a group.

Short answer
Name the muscle found in the human heart?

Cardiac muscle

Given is a diagram of a human blood smear. Study the diagram and answer the question that follows.
Name the components numbered 1 to 4.

The given diagram shows the microscopic view of a human blood smear:-

RBCs or Red blood cells are oval biconcave disc-shaped cells. It contains haemoglobin protein (iron-containing pigment) which helps in carrying oxygen.
WBCs or White blood cells (neutrophils) are also known as leukocytes. It helps to fight infections by attacking different microbes that enter the body. The most common WBCs in blood is neutrophils which have a multilobed nucleus.
Platelets or thrombocytes are biconvex discoid structures in the blood whose main function is to prevent bleeding by initiating blood clotting (with other coagulating factors).
Blood plasma is a pale yellow liquid which consists of all the blood cells along with salts and enzymes.

Give appropriate biological or technical terms for the following.
Squeezing out of blood cells from the capillaries into the surrounding tissues.

Diapedesis

What are bones made of ? Are the bones living or non-living ? Give reason.

Bones are compromised of protein and calcium phosphate. They are living growing tissues. They have their own blood vessels and are made of living cells, which help them to develop and to repair themselves.

What is the difference between ligament and tendon? What are their functions?

Two bones can be connected to each other by a type of connective tissue called the ligament. This tissue is very elastic. It has considerable strength. Ligaments contain very little matrix and connect bones with bones.
Tendons connect muscles to bones and are another type of connective tissue. Tendons are fibrous tissue with great strength but limited flexibility.

Define the term 'Tissue.'

Answer:

Tissue is a group of cells having similar structure and function together as a unit .
There are four main types of tissues in the body - epithelial , connective , muscle and nervous tissue .
All the body parts are made up of tissues including the organs.

Name different types of WBCs.

There are 2 main categories of WBCs.

Granulocytes, which are further classified into 3 different types:

Neutrophils - These are phagocytic cells which destroy foreign organisms entering the body and comprise of 60-65% of WBCs.
Eosinophils - These resist infections and are associated with allergic reactions. It comprises 2-3% of WBCs.
Basophils - These are the least (0.5-1%) among WBCs and are involved in inflammatory reactions.

Agranulocytes, which are further divided into 2 types:

Monocytes - These are also phagocytic cells which destroy foreign organisms entering the body and comprise of 6-8% of WBCs.
Lymphocytes - These are responsible for immune responses of the body and are comprised of 20-25% of WBCs.

Name a simple living mechanical tissue.

Collenchyma

Fill in the blanks with appropriate words.

Root hairs are formed from extensions of the ..........

Epidermal cells

"Abnormally large number of WBC's in the blood are usually an indication of some infection in our body." Comment on the statement.

Whenever there is an infection in the body, the immune system receives a signal to synthesize particular antibodies. In response to the quantity of germ-multiplication in the body, white blood cells multiply rapidly which enables it to produce more antibodies thereby stopping an infection on time. Consequently, abnormal numbers of WBCs are an indication of some infection in the body.

Name the tissue which connects muscle to a bone.

Tendon.

Very short answer type.
What is a ligament?

A dense fibrous connective tissue that connects bones at the joints and holds them in position is called ligament. Ligaments are present only at the joint between two bones.

Very short answer type.
Mark the odd one in the given series.
areolar tissue, blood, neuron, tendon

The odd one out is neuron because all the other options are connective tissues but neuron is nervous tissue.

Very short answer type.
How many types of muscles occur in the body of a vertebrate?

Three types of muscles are present in the body of a vertebrate: striated, non-striated and cardiac muscles. Striated muscles are mostly voluntary muscles. Non-striated muscles form the soft organs of the body. Cardiac muscles are seen in the heart.

Differentiate between erythrocytes and leucocytes of mammals.

Erythrocyte	Leucocyte
They are non-nucleated circular discs and appear biconcave in side view and has haemoglobin.	They are nucleated cells devoid of haemoglobin.
They donot have mobility of their own.	They are capable of amoeboid movement.
They are highly specialized to carry oxygen transport function	They are extremely important cells as they provide defense mechanism to the body against infections.

Which type of WBCs are called granulocytes and why?

A granulocyte is a category of white blood cells characterized by the presence of granules in their cytoplasm. They are also called polymorphonuclear leukocytes or polymorphonuclear neutrophils (PMN, PML or PMNL) because of the varying shapes of the nucleus, which is usually lobed into two or three segments

Differentiate between.
Hemopoiesis and hemolysis.

Hemopoiesis	Hemolysis
Formation of blood corpuscles is called hematopoiesis.	Destruction of worn out RBCs and the conversion of haemoglobin into bile pigments is called hemolysis.
It occurs in bone marrow, liver and yolk sac.	It occurs in liver and spleen.

What are the characteristics of cardiac muscle? Describe its specific function.

Heart, which pumps blood throughout the body, is made up of cardiac muscles.

The features of cardiac muscle are:

(i) Cardiac muscles are involuntary. They cannot be controlled by will.

(ii) Cardiac muscle cells are cylindrical, branched and uninucleate.

(iii) Cardiac muscles show rhythmic contraction and relaxation throughout the life.

Very short answer type.
Mark the odd one in each series.
neurolemma, dendrite, Z-band, myelin

Z-band is the odd one out here because it is a part of muscle tissue. Neurolemma, dendrite, and myelin are all parts of a neuron.

Give two main differences between unstriped and striped muscular tissues and give examples of each.

The two main differences between unstriped and striped muscular tissues are as follows:-

Striped/Striated/Skeletal/Voluntary muscles are long, cylindrical and unbranched while Unstriped/Unstriated/Smooth/Involuntary muscles are small and Spindle-shaped.
Striped muscles are multinucleate while unstriped muscles are uninucleate.
The example of striped(voluntary) muscles is locomotory muscles, tongue, pharynx, diaphragm, middle ear muscles, sheets of muscles of the abdominal wall under the skin.
The example of unstriped(involuntary) muscles are muscles of urogenital tracts, alimentary tracts, respiratory tracts, ducts of glands, blood vessels, ciliary muscles.

Describe the structure and the functions of three types of muscular tissue

Muscle tissue is a soft tissue that composes muscles in animal bodies and gives rise to muscles' ability to contract.

There are mainly three types of muscle tissue:-

1)Skeletal(Striated) Muscle:
Structure: Skeletal muscle is called "striated" because of its appearance consisting of light and dark bands visible using a light microscope. A single skeletal muscle cell is long and approximately cylindrical in shape, with many nuclei located at the edges (periphery) of the cell.

Function:

Movement of the skeleton under conscious control, including movement of limbs, fingers, toes, neck, etc.
Movement of tissues of facial expression under conscious control, e.g. ability to smile and to frown.

2)Smooth(Non-Striated) Muscle:

Structure: Unlike Skeletal and Cardiac muscle tissue, Smooth muscle is not striated. Smooth muscle fibres are small and tapered - with the ends reducing in size, in contrast to the cylindrical shape of a skeletal muscle. Each smooth muscle fibre has a single centrally located nucleus.

Function: Contractions of smooth muscle constrict (i.e. narrow = reduce the diameter of) the vessels they surround. This is particularly important in the digestive system in which the action of smooth muscle helps to move food along the gastrointestinal tract as well as breaking the food down further. Smooth muscle also contributes to moving fluids through the body and to the elimination of indigestible matter from the gastrointestinal system.

3)Cardiac(Semi-Striated) Muscle:

Structure: Cardiac muscle fibers are striated, branched (sometimes described as Y-shaped), and have a single central nucleus. These fibers are attached at their ends to adjoining fibers by thick plasma membranes called intercalated discs.

Function: Pumping of blood through the heart: Alternate contraction and relaxation of cardiac muscle pumps

De-oxygenated blood through the Right Atrium and Right Ventricle to the lungs, and oxygenated blood through the Left Atrium and Left Ventricle to the aorta, then the rest of the body.

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What roles do the dendrites, cell body, and axon play in communication of signals?

Dendrites and the cell body receive input signals and the axon conducts nerve impulses (action potentials) and transmits the message to another neuron or effector cell by releasing a neurotransmitter (acetylcholine) at its synaptic end bulbs.

Cell body connects the dendrites to the axon body. They are composed of different organelles like the nucleus, ribosomes, and Nissl's granules. These granules give colouration to the cell body.

Name the kind of tissue that forms the inner lining of blood vessels.

Simple squamous epithelium forms the inner lining of blood vessels. These are simple flat selectively permeable epithelial cells.

Differentiate between.
Neuron and nephron

Neuron is the basic unit of nervous system. Nephron is the structural and functional unit of kidney

Short/ Long answer type questions.
Give four differences between red and white muscle fibres.

Red muscle fibres	White muscle fibres
Dark red in colour due to the presence of more myoglobin.	Lighter in colour as they do not contain myoglobin.
Mitochondria more in number.	Mitochondria are less in number.
More blood capillaries.	Fewer blood capillaries.
Have a slow rate of contraction for longer periods.	Have a fast rate of contraction for short periods.

Example of red muscle fibres: flight muscles of kites and extensor muscles of the human back

Example of white muscle fibres: eyeball muscles, flight muscles of a sparrow.

Give the other name for white bloods cells.

White Blood Cells are known as Leukocytes as they are colourless due to lack of haemoglobin. They are short lived and involved in defense mechanism .

What is epidermis?

The epidermis is the upper or outermost layer of the two main layers of cells of the skin. It is made up of flat, scale-like cells called squamous cells. The lower part of the epidermis contains melanocytes which are the cells that produce melanin that gives colour to the skin.

Describe briefly the structure of a nerve cell.

Nerve cell is the basic functional unit of the nervous system. It is also called as neuron. It consist of cell body that contains nucleus and other cell organelles like mitochondria, endoplasmic reticulum, Golgi apparatus. It consists of tiny branches called dendrites all over the cell body. Dendrites receive signals from other cells and pass them toward the cell body. Axon is the single long output from the cell body. It carries information from the cell body over long distances quickly. Axon terminal is present at the end of axons. It makes the actual connection to other neurons. In some never cells, axons are covered by myelin sheath. It acts as insulation for the axon. The gaps between myelin sheath cells are called Nodes of Ranvier. Schwann cell plays important role in myelinating the axons of the PNS.

Give three features of cardiac muscles.

Cardiac muscles are found in heart. Characteristics of cardiac muscles are (any three):

The muscles have striations just like skeletal muscles by having actin and myosin filaments that are arranged into sarcomeres.
The muscles have an involuntary function as their functioning is not under our control.
The muscles are myogenic - means the contractions are generated within the muscles.
The muscles consist of a network of interconnected muscle fibres each of which has numerous mitochondria, myofibrils with sarcomere and many nuclei.
The muscle tissue has no regenerative capacity.

Why do the thigh muscles get tired soon, but not the muscles of the heart?

Thigh muscles are skeletal muscles whereas muscles of the heart are cardiac muscles. The cells of cardiac muscles have a greater number of mitochondria than the cells present in skeletal muscle. So, the cells of cardiac muscles get plenty of energy, produced by mitochondria.

Hence, thigh muscles get tired soon but not the muscles of the heart.

Describe the functions of the following components of the transport system.
(i) Blood
(ii) Lymph

Blood is a fluid connective tissue. It is composed of plasma and formed elements such as red blood cells (RBC), white blood cells (WBC) and platelets. The major functions of blood include;

Transportation of respiratory gases and digested food materials.
Transportation of waste materials.
Transportation of hormones.
Maintaining pH and water balance.
Regulating body temperature.

Lymph is a colorless fluid derived from filtration of blood through capillary walls in the tissue forming the interstitial fluid. It is circulated throughout the body through lymphatic vessels when this interstitial fluid is collected by lymphatic capillaries. The major functions of lymph include;

Serving as middlemen between blood and tissue to facilitate transportation of substances and gases to one another.
Transportation of digested fats and fat-soluble vitamins. Lymph also absorbs fats and lipids from small intestines and transfers to blood as small droplets called chylomicrons.
Storage of lymphocytes which fight against infections by bacteria and other foreign particles.

What is the function of myelinated sheath in a neuron?

Myelin sheath is a sheath found around some neurons. It consists of fat-containing cells. Its main function is to protect and insulate the axon for efficient impulse transmission. This results in the increased rate of transmission of electric signals.

What is the use of tissues in multicellular organisms?

Tissue is a collection of cells with a similar structure and function.
In multicellular organisms, the body has levels of organization that build on each other. Cells make up tissues, tissues make up organs, and organs make up organ systems.
This complex level of organization enables the division of labour.
For example, blood tissue helps in the transportation of vital substances in our body whereas muscular tissue helps in body movement.

What is a complex permanent tissue? Write the different types of complex permanent tissues.

Complex tissues are made of more than one type of cells. All these cells coordinate to perform a common function. Xylem and phloem are examples of such complex tissues. They are both conducting tissues and

constitute a vascular bundle.

Give a brief account on neurons.

Neuron or nerve cell is the fundamental unit of the nervous system. The major function of the neuron is to receive and integrate the incoming signal and then based on that transfer signal to other neurons, muscles or glands.

The basic structure of a nerve cell/ neuron is majorly classified into three parts - dendrites, cell body/ soma, and axon.

Neurons receive and process the incoming information using dendrites and the cell body. The incoming signal can be either excitatory or inhibitory. Each neuron contains more than one set of dendrites. Thus neuron receives multiple information at the same time using their dendritic trees. Whether a neuron gets excited or not at a time depends on the sum total of all excitatory and inhibitory signals it received at that point in time.

If the neuron gets excited, the impulse, or the action potential, is conducted down to the axons. The axon of some nerve cells (myelinated neurons) has myelin sheath surrounded at regular intervals. Myelin sheath, formed by Schwann cells, creates localized insulation zones thereby enhancing the conduction speed of action potential.

The axon splits into multiple branches with each branch endings develop swellings, called an axon/ synaptic terminals. These synaptic terminals create synaptic junctions that connect the neuron to another neurons or effector muscle cells and enables transmission of information in-between two connected cells.

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What are the types of muscular tissue? Explain in detail.

Based on the location, there are three types of muscular tissues. They are as follows:

1. Skeletal muscles

These muscles are related to skeletal components of the body.
They have striped appearance, hence, they are also called straited muscles.
These muscles are also called voluntary muscles because their activities are under voluntary control of the somatic nervous system.
These muscles are primarily involved in locomotory actions and changes of body postures.

2. Smooth muscles-

Smooth muscles or nonstraited muscles are so called because they do not exhibit any striation and are smooth in appearance.
They are also known as visceral muscles because they are located in the inner walls of hollow visceral organs of the body like the alimentary canal, reproductive tract, etc.
Their activities cannot be voluntarily controlled and are therefore called involuntary muscles.
They assist, for example, in the transportation of food through the digestive tract and gametes through the genital tract.

3. Cardiac muscles-

As the name suggests, these muscles are the muscles of the heart.
Many cardiac muscle cells assemble in a branching pattern to form a cardiac muscle.
They are striated and involuntary in nature.

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Draw a flow chart to show the types of blood cells.

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Why are the voluntary muscles also called striated muscles?

Striated muscles are the skeletal muscles which are also known as voluntary muscles. They are called voluntary muscles because their action is under the control of the somatic nervous system and their movement can be controlled by us (Eg: Bicep muscles), unlike as in the case of involuntary muscles (Eg: cardiac muscles). The muscle fibers of striated muscles are multinucleated and cylindrical. They appear striated due to the presence of alternate light and dark bands when viewed through the microscope.
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Tissue that stores fat in our body is ________

The tissue that stores fat in humans is called 'adipose tissue'. It is composed of specialized cells called adipocytes. Its main function is to store energy in the form of fat and also act as a shock absorber (cushion) and insulator. Adipose tissue is basically located under the skin (subcutaneous fat), but is also present around internal organs (visceral fat), between muscles and in the bone marrow.

Name the part of the neuron where information is acquired.

The part of neuron where the information acquired is the end of dendrites.

Dendrites are specialized extensions of the cell body. They function to obtain information from other cells and carry that information to the cell body.

Draw a neat labelled diagram of non- straited muscle.

Image result for Draw a neat labelled diagram of non- striated muscle

Explain the basic criteria for classification of permanent tissue of the plant.

The cells of meristematic tissue divide to a limited extent, and become specialized for a specific function. This process is referred to as differentiation. The cells lose their ability to divide after a successful differentiation, and it results in the formation of permanent tissue. There are two types of permanent tissue; simple permanent tissue and complex permanent tissue.

Simple permanent tissue contains cells that possess the same structure and function. It is mainly of three types-parenchyma, sclerenchyma and collenchyma. Complex permanent tissue consists of different types of cells, but all of them act as a single unit to perform a particular function. It is mainly of two kinds- xylem and phloem.

Explain the structure of muscle fiber seen in walls of visceral organs

The visceral organs are made up of smooth muscle or unstriated muscles which are present in the walls of hollow organs like the urinary bladder, uterus, stomach, intestines etc.
Smooth muscle cells have a single nucleus and are spindle-shaped.
Its sarcoplasm consists of actin and myosin along with dense bodies in the sarcolemma which anchor the thin filaments.
A network of intermediate filaments is present in them that pulls the sarcolemma toward the fibers i.e it helps in contraction.

Draw a neat labelled diagram of non-striated muscle.

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Classify simple epithelial cells on the basis of shape and position in the body.

1) Simple squamous-

They are polygonal in shape.
They are found lining areas where passive diffusion of gases occurs.
Eg- skin, walls of capillaries, linings of the alveoli of the lungs etc.

(2) Simple cuboidal-

They are cuboidal in shape.

They are secretory, absorptive or excretory in functions.
Eg- small collecting ducts of kidney, pancreas, and salivary gland.

(3) Simple columnar-

They are long and elongated.

They can cell can be secretory, absorptive, or excretory.
They can be 1) Ciliated or 2) Non-ciliated.
Ciliated columnar is found in fallopian tube and uterus.
Non-ciliated epithelium also possesses microvilli.

(4) Pseudostratified columnar epithelium-

They can be ciliated or non-ciliated.
The ciliated type is also called respiratory epithelium as it is almost exclusively confined to the larger respiratory airways of the nasal cavity, trachea, and bronchi.

Describe location, structure and function of the nervous tissue.

Nervous tissue, also called neural tissue or nerve tissue, is the main tissue component of the nervous system. The nervous system regulates and controls bodily functions and activity and consists of two parts: the central nervous system (CNS) comprising the brain and spinal cord, and the peripheral nervous system (PNS) comprising the branching peripheral nerves. It is composed of neurons, or nerve cells, which receive and transmit impulses, and neuroglia, also known as glial cells or glia, which assist the propagation of the nerve impulse as well as provide nutrients to the neurons.

Nervous tissue is made up of different types of nerve cells, all of which have an axon. An axon is the long stem-like part of the cell that sends action potential signals to the next cell. Bundles of axons make up the nerves in the PNS and tracts in the CNS. Functions of the nervous system are sensory input, integration, control of muscles and glands, homeostasis, and mental activity.

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Write a note on areolar connective tissue

Areolar connective tissue is found between the skin and muscles, around blood vessels and nerves and in the bone marrow. It fills the space inside the organs, supports internal organs and helps in repair of tissues.

Name a layer of large flat cells which fits closely as to edge like tiles in a floor.

A layer of large flat cells which fits closely like tiles in a floor is called Simple squamous epithelium. It is also called pavement epithelium. It is found in places where rapid diffusion is required, such as capillaries, alveoli, glomeruli.

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I) What are the different types of muscular tissues?
ii) Write two differences between these tissues.
iii) What are unique characters of cardiac muscles?

Skeletal muscle	Smooth muscle	Cardiac muscle
voluntary muscle	Involuntary muscle	Involuntary muscle
They allow controlled movement of parts in which it is present, for example, hands, legs, shoulders etc.	They are present in the gastrointestinal tract	Cardiac muscles as the name suggests are present in the heart.

There are three different types of muscular tissue, cardiac muscle, smooth muscle & skeletal muscle.

differences between these tissues are given in the table above.

Cardiac muscles are striated, branched & have a central nucleus, these are attached at their ends to adjoining fibers by intercalated discs.

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From which organ do erythrocytes originate?

Erythropoiesis is the process of formation of red blood cells. The red blood cells are formed from a common myeloid progenitor cell. In children it occurs in all the bones having red bone marrow, liver and spleen. In adults, after the age of 20 years it occurs in red bone marrow of long bones.

Pneumocyte Type-1 of alveoli are example of _________.

Pneumocyte Type-1 of alveoli are the examples of squamous cells. This type of cell helps in gaseous exchange within the alveoli of the lungs. It is a very large thin cell stretched over a very large area.

Write a note on Cardiac Muscles?

Cardiac muscles are the special types of involuntary muscles found only in the heart. These are striated due to the presence of sarcomere. They are branched and each cell of these fibers has a single nucleus, means that they are uninucleated. They continue to perform the contraction throughout the life of an organism.

What are WBC, RBC and platelet?

RBC or Erythrocytes	WBC or Leucocytes	PLATELETS or Thrombocytes
They help to carry oxygen from the lungs to the body tissues and carbon dioxide as a waste product away from the tissues and back to the lungs.	They help to fight infection and protects the body against both infectious disease and foreign invaders.	Their function is to react to bleeding by initiating a blood clot.

The cellular portion of blood consists 3 important components- red blood cells, white blood cells and platelets.
These blood cells are produced in the bone marrow.

Differentiate between the white blood cells and red blood cells.

RED BLOOD CELLS	WHITE BLOOD CELLS
1) They are called erythrocytes.	1) They are called leucocyytes.
2) Its main function is to carry oxygen from the lungs to the body tissues and carbon dioxide (the waste product) away from the tissues and back to the lungs.	2) They are the cells of the immune system which help to protect the body against infectious disease and foreign invaders.

Write a note on aerolar connective tissue.

Areolar connective tissue are type of connective tissue found below the skin, around blood vessels and nerves and in the bone marrow. It is made up of extracellular matrix and cells. The matrix contains fibroblast, histocytes, mast cells and small lymphoid cells. It also contains 2 types of fibres, namely inelastic white collagen fibres and elastic yellow elastin fibres. It performs many functions. It basically provides support, strength and elasticity. The histocytes protect against infection. Mast cells help in treating allergic reactions.
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The number of bones in an adult human body is _________.

The total number of bones in the human body is 206.

What is the main function of white blood corpuscle?

White blood cells are the cells of the immune system that are involved in protecting the body against infectious diseases and foreign substances. They are broadly classified as Granulocytes and Agranulocytes

Explain Structure of striated muscle tissue.

Striated muscles are also called skeletal muscles as they are mostly attached to bones and help in body movement. Under the microscope, these muscles show alternate light and dark bands or striations when stained appropriately. As a result, they are also called striated muscles. The cells of this tissue are long, cylindrical, unbranched and multinucleate (having many nuclei).

Classify the following into cells, tissue, and organ.

skin, fat cell, RBC, blood, ear, muscle

Cell - fat cell, RBC
Tissue - muscle, blood
Organ - skin, ear

Which one is largest and smallest
(a) Eosinophil
(b)Basophil
(c)Neutrophil
(d)Monocyte
(e) T-lymphocyte

Leucocytes are also known as white blood cells (WBC) as they are colourless due to the lack of haemoglobin. They are nucleated and are relatively lesser in number which averages 6000-8000 mm$$^{-3}$$ of blood. We have two main categories of WBCs – granulocytes and agranulocytes.

Neutrophils, eosinophils and basophils are different types of granulocytes, while lymphocytes and monocytes are the agranulocytes.

Monocytes are the largest type of WBCs while lymphocytes are smallest.

Write a note on squamous epithelium.

Squamous epithelium is made of a single thin layer of flattened cells with irregular boundaries and is found in the inner lining of the oesophagus and mouth. It is also found on the skin. Skin epithelial cells are arranged in many layers to prevent wear and tear. This type of epithelium is called stratified squamous epithelium.

Name of the protein present in the bone matrix.

Collagen is the protein which is found in the bone matrix. This triple helical structure is very strong and prevents the bone from being broken down by enzymes.

Full form of RBCs

Red Blood Corpuscles

Write name of muscle responsible for movement of hairs.

The smooth muscles that are attached to the hair which are responsible for their movement are arrector pilli. They extend from the superficial dermis of the skin to the dermal root sheath around the side of the hair follicle. In its normal position, hair emerges at an angle to a surface of the skin. But under the certain condition like stress, cold etc the nerve ending stimulate the pilli muscles to contract which pulls the hair shafts perpendicular to the skin surface. This action is called goosebumps. When the impulse is not present their anymore than the pili retracts and the hair goes back to its flattened position on the skin.

At intervals, myelinated nerve fibres possess unmyelinated areas called ______.

The myelinated nerve fibres are enveloped with Schwann cells, which form a myelin sheath around the axon. At intervals, myelinated nerve fibres possess unmyelinated areas called node of Ranvier. They provides faster transmission of electrical impulses through axon.
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Name the three kinds of blood cells.Which amongst them has nucleus?

There are three types of living cells in blood: red blood cells (or erythrocytes), white blood cells (or leukocytes) and platelets (or thrombocytes). A white blood cell, also called leukocyte or white corpuscle, a cellular component of the blood has a nucleus which defends the body against infection and disease by ingesting foreign materials and cellular debris, by destroying infectious agents.

Draw a diagram of the human nerve cell. Justify its shape with regards to its function.

Neurons carry information from the brain and spinal cord to the rest of the body by means of electrical signals. Since electrical signals travel much faster than chemical signals, neurons are long and thin to minimize the number of slower chemical signals that would be required between links in a chain of many shorter neurons.
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Name the parts labelled $$a, b, c, d, e, f, g$$ and $$h$$ in the neuron drawn below.

The given diagram is of Neuron anatomy.

a. Dendrite.

b. Cell body.

c. Nucleus

d. Axon.

e. Myelin sheath.

f. Schwann cell.

g. Node of Ranvier.

h. Axon terminal.

Identify the odd word and explain why it is odd:
Cartilage, Bone, Tendon, Cardiac Muscle

Cartilage, bone, and tendon are all part of the connective tissues. Cardiac muscle also known as heart muscle is a type of striated muscle tissue.

So, cardiac muscle is the odd one.

Give reasons for this sentence:
A mature erythrocyte lacks nucleus and mitochondria.

A mature erythrocyte lacks nucleus and mitochondria so as to make place for the accommodation of more hemoglobin and hence more oxygen molecules. Lack of such organelles also provides the peculiar biconcave appearance of RBCs that aids in efficient diffusion.

Give reasons for the following
Leukocytes are called soldiers of our body.

The white blood cells or leukocytes help provide immunity by destroying or killing foreign pathogens and antigen and thereby provide protection from diseases and infections. They are therefore called the soldiers of our body.

Name the tissue responsible for the movement in our body.

Explanation:

Muscular tissue is made of elongated cells, also called muscle fibers.
This tissue helps the body in movement.
Muscle tissue has the property or ability to shorten or contract in order to produce movement of the body parts.
These Muscle tissues are well supplied with blood vessels.
Muscle tissue can be categorized into skeletal muscle tissue used for locomotion, smooth muscle tissue used in internal organs, and cardiac muscle tissue.

Define the term tissue with respect to plants.

A tissue is a group of cells having a common origin and usually performing a common function. Vascular tissue (xylem and phloem) is an example of complex tissue and similarly. A simple tissue is made of only one type of cell. The various simple tissues in plants are parenchyma, collenchyma, and sclerenchyma.

If there is increase in RBC's count in Ramesh's blood, then he is suffering from which condition?

Ramesh is suffering from a condition called as polycythemia vera which causes the elevation in RBCs production in bone marrow due to which he is susceptible to have a heart attack, stroke, etc.

Give one word for the following.
An iron containing protein present on the surface of red blood cells.

Hemoglobin

How are simple tissues different from complex tissues in plants?

Simple tissue	Complex tissue
They are made up of only one type of cells.	They are made up of more than one type of cell.
They are distributed in all regions of the plant.	They are found only in the vascular bundles.
They perform storage functions such as parenchyma, mechanical strength Sclerenchyma etc	They are involved in transport by the conduction of food and water. E.g: Phloem and Xylem

What is erythroblastosis?

Erythroblastosis fetalis refers to life-threatening disease of a fetus or a new born infant in which the immune system of the mother produces antibodies against the red blood cells of the infant resulting in the destruction of the red blood cells of the fetus. This is because of the Rh incompatibility between the mother and the fetus and may result the fetus to suffer from severe anaemia, brain damage or even death in extreme cases.

Name the muscle which is commonly found in visceral organs.

Smooth muscles

Distinguish between red muscle fibres and white muscle fibres.

RED MUSCLE FIBERS(Tonic)	WHITE MUSCLE FIBERS(Twitch)
1. These are thin and smaller in size.	1. These are thick and larger in size.
2. They are red in colour as they contain a large amount of myoglobin.	2. They are white in colour as they contain a small amount of myoglobin.
3. They contain numerous mitochondria.	3. They contain less number of mitochondria.
4. They carry out slow and sustained contractions for a long period.	4. They carry out fast work for a short duration.
5. Sarcoplasmic reticulum is moderately developed.	5. Sarcoplasmic reticulum is well developed.
6. The fibres are supplied with abundant blood capillaries.	6. They are moderately vascularised.
7. Lactic acid does not accumulate.	7. Lactic acid accumulates.
8. They perform aerobic respiration.	8. During strenuous exercise, it switches over to anaerobic respiration.

Write the function of the following.
Chordae tendineae.

The chordae tendineae (tendinous cords), colloquially known as the heart strings, are tendon-resembling fibrous cords of connective tissue that connect the papillary muscles to the tricuspid valve and the mitral valve in the heart.

How many muscles are present in human body approximately?

There are more than 600 muscles in the human body. The three main types of muscle include skeletal, smooth and cardiac muscles.

Give importance/functions of Erythrocytes.

RBCs or erythrocyes contain hemoglobin which plays an important role in the transport of Oxygen from the lungs to the various tissues. It also carries Carbon Dioxide from the tissue back to the lungs.

The diagram given alongside is the external view of the human brain. Study the same and answer the question that follow.
What is the structural and functional unit of nervous system?

Neuron

Name the type of muscle fibers that has automatic rhythmicity.

The type of muscle fiber that has automatic rhythmicity is Cardiac muscle. Cardiac muscle fiber has automatic rhythmicity. It is a contractile tissue present only in the heart. When one cell in cardiac tissue receives a signal to contract, its neighbor cells are also stimulated to contract.

Give appropriate biological/technical terms for the following.
The tissue which stores fat.

Adipose tissue

Find out the correct matches:
Group 'A' Group 'B'
Heart beats a. 350 ml
RBC b. 7.4
WBC c. $$37^oC$$
Blood Donation d. 72
Normal body e. 4-6 $$millions /mm^3$$
pH of oxygenated blood f. 5000-6000 / $$mm^2$$

Group 'A'	Group 'B'
1. Heart beats	d. 72 (per minute)
2. RBC	e. $$4-6\ millions/mm^3$$
3. WBC	f. 5000-6000 / $$mm^3$$
4. Blood donation	a. 350 ml
5. Normal body Temperature	c. $$37^oC$$
6. pH of oxygenated blood	b. 7.4

Name the following :
Tissue that connects muscle to bone in human.

Tendons

Name the following:
Tissue that stores fat in our body.

Adipose tissue

What different types of cells will you see when you observe a drop of blood under a microscope? What are their functions?

Answer :

If we observe drop of blood and microscope, we will observe the following cells -

i) Red blood cells or erythrocytes - the red blood cells contains iron and carries oxygen in the form of oxygen hemoglobin from lungs to all parts of the body.

ii) White blood cells or leukocytes - WBC's are primary defense against infection they attack and destroy germs that enter of the body.

iii) Platelets or thrombocytes - platelets help in stopping the blood by sticking to opening of the broken blood vessel and attract More platelets to form a clot.

What are the component of the transport system in human beings? What are the functions of these components?

The main components of the transport system in human beings are the heart, blood, and blood vessels.

• The heart pumps oxygenated blood throughout the body. It receives deoxygenated blood from the various body parts and sends this impure blood to the lungs for oxygenation.

• Being a fluid connective tissue, blood helps in the transport of oxygen, nutrients, CO2, and nitrogenous wastes.

• The blood vessels (arteries, veins, and capillaries) carry blood either away from the heart to various organs or from various organs back to the heart.

Which structure protects the plant body against the invasion of parasites?

Epidermis has thick cuticle, trichomes and dermal tissue to protect the plant from the invasion of parasites and other harmful agents.

Xylen & phloem are described as ________

Conducting tissues

Distiguish between the following pairs of terms:
Thrombocyte and Erythrocyte

Thrombocytes or platelets are cytoplasmic fragments with different shapes that play an important role in blood coagulation.

Erythrocytes or RBCs are discoidal cells that lack nucleus and most organnelles. They contain an iron containing pigment called hemoglobin that binds reversibly with Oxygen and Carbon dioxide and helps in their transport.

Fill in the blanks.
Lining of blood vessels is made up of _____ tissue.

Lining of blood vessels is made of squamous epithelial tissue.

Squamous epithelium helps in exchange of gases between the alveoli and the capillaries and between capillaries and tissues.

Write a short note.

Meristematic tissue.

Meristematic tissues are the cells or groups of cells that have the ability to divide. These cells divide continuously and thus helps in increasing the length and thickness of the plant. Depending upon the position, meristematic tissues can be classified as:
$$\bullet$$ Apical Meristem: It is present at the growing tips of stem and roots. It increases the length of the plant's body. The apical meristems produce three kinds of primary meristems i.e., protoderm, ground meristem, and procambium.
$$\bullet$$ Intercalary Meristem: It is present at the base of the leaves. This meristem helps in the elongation of internodes.
$$\bullet$$ Lateral Meristem: It is present at the lateral regions of the stems and roots which bring about an increase in the width of the plant body. These are of two types: cork cambium and vascular cambium.

The following statement is wrong. Rewrite it correctly by changing either one or two words.

Simple squamous epithelium is present in respiratory tract.

Simple squamous epithelium is present in oesophagous.

Why are xylem and phloem called complex tissues? How are they different from one other?

Both xylem and phloem consist of more than one type of tissue, which coordinate to perform a common function. Hence, called complex tissue.

xylem	phloem
Consists of tracheids, vessels, xylem, parenchyma and xylem fibres.	Consist of sieve tubes, companion cell, phloem parenchyma and phloem fibres.
They transport water and minerals vertically from soil to aerial parts of the plant.	They transport food from leaves to other parts of the plant.
All of the tissues except xylem parenchyma are dead. Conduction is unidirectional from roots to leaves.	Most of the tissues except phloem fibres are living. Conduction is bidirectional, from source to sink.

Sclerenchyma is a _____________ permanent tissue.

Sclerenchyma is a simple permanent tissue as it is made up of only one type of cell. The cells of this tissue are dead. They are long and narrow as the walls are thickened due to lignin.

Why is epidermis important for the plants?

Epidermis is important for plants due to the following reasons :
(i) It gives protection
(ii) Helps in gaseous exchange
(iii) Checks water loss
(iv) Root hair arising from epidermis helps in absorption of water and minerals.

Name any two simple and two complex permanent tissues in plants.

Two simple and two complex permanent tissues found in plants are as follows:
Simple tissues: Parenchyma, collenchyma and sclerenchyma.

Complex tissues: Phloem and Xylem.

Write the name of the following tissue.

The tissue lining the inner surface of the mouth.

Tissue lining inner surface of mouth - squamous epithelium.

Why do we get a crunchy and granular feeling when we chew pear fruit?

Pear contains cells of sclerenchyma which are small, rounded and called stone cells. They are hard with highly thickened cell wall. These cells give the crunchy and granular feeling when we chew pear fruit.

Differentiate between meristematic and permanent tissues in plants.

Meristematic	Permanent
Cells of this tissue divide throughout their life.	They lose the ability to divide to take up specific function.
They are located at specific regions of the plant viz: apical, lateral, intercalary.	They are distributed throughout the plant body.
Cells of this tissue are very active, have dense cytoplasm, thin walls and prominent nuclei. They lack vacuoles.	They are vacuolated, vary in shape and size. Their cell wall may be thick
Cell wall is cellulosic	Cell wall is made up of cellulose/ lignin/ suberin.

Fill in the blanks:
Bone possesses a hard matrix composed of _ and _.

$$\textbf{Explanation:}$$

$$\bullet$$ The cells of connective tissue are embedded in a matrix.

$$\bullet$$ The bone connective tissue provides a structural framework to the body.

$$\bullet$$ The matrix of the bone is hard. Bone cells are embedded in a hard matrix that is composed of calcium and phosphorus compounds.

$$\textbf{Conclusion:}$$ Thus, bone possesses a hard matrix composed of calcium and phosphorus.

Name any two simple and two complex permanent tissues in plants.

The tissues are named as follows;

Simple: Parenchyma and Collenchyma
Complex: Xylem and Phloem.

Write a short note on RBCs.

RBCs comprise $$99$$% of blood cells. RBCs contain a protein called haemoglobin which imparts red colour to them They lack nucleus. The life span of RBCs is $$120$$ days.

Give reasons.

Muscles should be strong and efficient.

Our muscles should be strong and efficient because they carry out various vital functions in our body. From helping us to breathe, digest food to helping us in walking and lifting weights, muscles play an important role. If our muscles are not strong enough we would get tired easily and feel fatigued. It is required to keep them in a healthy state by regular exercising and taking proper diet.

What are the functions of areolar tissue?

Answer:

Areolar tissues is a connective tissue in which fibers are loosely arranged in a net or meshwork. The tissue consists of collagenous and elastic fibers, ground substance, and connective tissue cells.

Functions of Areolar Tissue are as follows:

Acts as a binding tissue.

Bind the skin with muscles.

Bind the blood vessels and nerves with other structures of body.

Helps in healing of wounds.

Grey matter is present in which organ?

Grey matter is present in the brain

How are simple tissues different from complex tissues, in plants?

Simple tissues are made up of only one type of cells, which look like each other. On the other hand. complex tissues are made up of more than one type of cells. Parenchyma, collenchyma and sclerenchyma are examples of simple plant tissue, whereas xylem and phloem are examples of a complex tissue. Simple tissues are protective and supportive in function. Complex tissues conduct water, minerals, and nutrients from roots and leaves to different parts of the plant.

Define Tissues? Describe the simple tissues found in plants with a diagram?

Tissues: A tissue is a group or collection of similar cells, which work together to achieve a particular function and have a common origin. Blood, phloem and muscles are examples of tissues.
$$*$$ Simple tissue: These are made up of only one type of cells. This type of tissue is similar in structure and function.
Simple tissues are further classified into three types:
1. Parenchyma
2. Collenchyma
3. Sclerenchyma

(1) Parenchyma: These are the simplest form of tissues with little specialisation. They have relatively unspecialised cells, with thin cell walls. They are loosely packed with inter-cellular spaces. This tissue provides support to plant, store food and allows the exchange of gases.

(2) Collenchyma: Collenchyma, being a strong and flexible tissue, has living and thick-walled cells; thickenings are present at the corners of the cells and contain cellulose and pectin; lignin is never present. Intercellular spaces are absent. Cells may be circular, oval or polygonal in shape.
A few chloroplasts may be present in the cells. Collenchyma is present in the peripheral regions of stem and leaves. Collenchyma is mainly a mechanical tissue and provides mechanical strength and elasticity to the growing stems.

(3) Sclerenchyma: Sclerenchyma is a strengthening tissue. Cells are dead and possess hard, rigid, very thick lignified walls; lignin is a waterproof material. Intercellular spaces are absent. Sclerenchyma cells are of two types-fibres which are long, narrow, pointed cells, and sclereids which are shorter, isodiametric or irregular cells; sclereids are also called stone cells or grit cells. The walls of sclerenchyma cells contain oblique thin areas, called pits. Sclerenchyma is a mechanical and protective tissue.
2035515_1838369_ans_25565473f4864524937cca1a23b84040.png

2035515_1838369_ans_25565473f4864524937cca1a23b84040.png

Write a short note on xylem.

Xylem is complex tissue as it consists of both parenchymatous and sclerenchymatous cells. It is composed of four elements:
(a) Tracheid: It is a non-living, elongated cell with tapering ends. The wall is highly thickened with lignin, except at certain circular spots known as pits.
(b) Vessel: It is a non-living cell with lignified walls. Tracheids and vessels are the main conducting elements in the xylem.
(c) Xylem parenchyma: It consists of a living cell and performs the function of storage.
(d) Xylem fibre: It is a non-living, thick-walled cell which provides mechanical support.

The stomatal pore is guarded by two kidney shaped guard cells. Name the epidermal cells surrounding the guard cells. How does a guard cell differ from an epidermal cell? Use a diagram to illustrate your answer.

1766397_1841846_ans_9cda0db96c464dd89151d5dfbc99e9c4.png (464×233)

$$\textbf{Explanation:}$$

$$\bullet$$ Few epidermal cells, in the vicinity of the guard cells become specialised in their shape and size are called as subsidiary cells.

$$\bullet$$ Differences between guard cells and epidermal cells are as follows:

Guard cells	Epidermal cells
1. They are kidney or dumbbell shaped.	1. They are barrel shaped.
2. They have chloroplast.	2. They do not have chloroplast.
3. They are smaller in size	3. They are larger in size.
4. The outer wall of guard cells are thin and the inner walls are highly thickened.	4. Cell wall is uniform and thin.
5. They carry out the process of photosynthesis.	5. They do not carry out photosynthesis.

What are the two basic types of plant tissues?

The two basic types of plant tissues are:

Meristematic tissue
Permanent tissue

Write the appropriate type of tissues in Column B according to the function mentioned in Column A:
Column A Column B
(a) Secretion and absorption ----
(b) Protective covering ----
(c) Linking and supporting framework ----

(a) Simple columnar epithelium
(b) Stratified epithelium
(c) Connective tissue

Product of photosynthesis is transported from the leaves to various parts of the plants and stored in some cell before being utilised. What are the cells/ tissues that store them?

$$\textbf{Explanation:}$$

$$\bullet$$ The product of photosynthesis is stored in the leucoplast of parenchyma cells in various parts of the plant like- tuber, bulb, roots, seeds etc.

$$\bullet$$ Leucoplast can be of different types depending on the basis of stored food material-

1. Amyloplast- It stores starch. Example: Potato

2. Aleuroplast- It stores protein. Example: Maize

3. Elaioplast: It stores fat/lipid. Example: Embryonic leaves of Oil seeds

Epidermal cells are often modified to perform specialized functions in plants. Name some of them and the function they perform.

$$\textbf{Explanation:}$$

Some of the modifications of epidermal cells and their functions are as follows:

$$\bullet$$ Root hair: They are the unicellular elongations of the epidermal cells. It increases the surface area for absorption of water and minerals.

$$\bullet$$ Trichomes/Stem hair: They are usually multicellular. They may be branched or unbranched and soft or stiff. They may even be secretory. Trichomes also help in preventing water loss due to transpiration.

A major percentage (97%) of $$O_2$$ is transported by RBCs in the blood. How is the remaining percentage (3%) of $$O_2$$ transported?

The remaining 3% of oxygen is transported in dissolved state through plasma.

What is the epidermal cell modification in plants which prevents water loss?

$$\textbf{Explanation:}$$

$$\bullet$$ Certain epidermal cells along the veins modify themselves into large, empty, colourless cells called as bulliform cells.

$$\bullet$$ These are found in grasses.

$$\bullet$$ When these cells in the leaves have absorbed water and are turgid, the leaf surface is exposed.

$$\bullet$$ When they are flaccid due to water stress, they help in rolling-in of the leaves to minimise water loss.

Name the plant tissue which helps in carrying the food to different parts.

Phloem - A complex permanent tissue that helps in carrying the food to different parts of the plants.

What do xylem vessels carry?

The water and minerals absorbed by the roots to the stem and leaves are carried by the xylem vessels.

Why is it easier to culture meristems compared to permanent tissues?

Merismatic cells have the capability of cell division while cells of permanent tissues do not have this capacity. Hence, it is easier to culture meristems as compared to permanent tissues.

Write one speciality of Striated muscle

Striated muscle are under the control of will and are composed of long fibers that are striated(dark and light band of fibers running across the fiber) and are multi -nucleated.

Name one place each in living organisms where the following tissue is located:
Meristematic tissue

Meristematic tissue is located at the root and stem apices.

Give one word for the following:
A group of similar cells performing a specific function.

A group of similar cells performing a specific function- Tissue

For ex. Epithelial tissue, Connective tissue, Muscle tissue.

Give the technical term for the following:
The category of plant tissues that have lost their ability to multiply.

The category of plant tissues that have lost their ability to multiply are the permanent tissues.

Write one speciality of each one of the following:
Bone

Bone is a hard and porous tissue. It consists of osteoblasts(living cells) and a rigid matrix of inorganic salts of calcium and phosphorous.

Give the technical terms for the the type of tissues which are involved in the upward movement of water and dissolved materials from the roots to other parts of the plant

Xylem

Write one speciality of each one of the following:
Cardiac muscle

Cardiac muscle is involuntary in nature, found only in the walls of the heart. These muscles have cylindrical uninucleate cells .

Give the location of the following muscle :
Unstriated muscles

Unstriated muscles are form the walls of intestine, muscles of the iris of the eye etc.

Study the diagram given below and the answer the questions that follow:

(a) Identify the cell.
(b) Name the parts labelled 1,2,3,4,5, and 6.
(c ) Where is this cell likely to be found in the human body and what is its function?

(a) The cell is the neuron or the nerve cell

(b) The labelled parts are:
1 – Dendrite
2 – Axon
3 – Nucleus
4 – Perikaryon
5 – Neurilemma
6 – Axon endings

(c) In the human body, the nerve cell is observed in the nervous system.
Function:

Transmission of messages from one to another body part
It is linked with the response and perception in animals.

Name the three kinds of muscles found in the human body. In each case, name one region in the body where they are found.

The three types of muscles present in the human body are:

Skeletal muscle - they are found in biceps.
Smooth muscle - are found in the Intestines and stomach.
Cardiac muscle - is found in the Heart.

Differentiate between cells of:
Meristematic tissue and permanent tissue

$$\begin{array}{|l|l|l|}\hline {\text { Properties }} & {\text { Meristematic tissue }} & {\text { Permanent tissue }} \\\hline \text { Cell division } & \text { Can divide } & \text { Cannot divide } \\\hline \begin{array}{l}\text { Intercellular } \\\text { space }\end{array} & \text { Absent } & \text { intercellular spaces may or may not be present } \\\hline\end{array}$$

Name the kinds of cells found in the surface of the human skin.

Surface of the human skin is made of stratified squamous epithelium.

A stratified squamous epithelium consists of squamous (flattened) epithelial cells arranged in layers upon a basal membrane. Only one layer is in contact with the basement membrane; the other layers adhere to one another to maintain structural integrity.

Name the kinds of cells found in the following places:
Brain

Neurons are the cells found in the brain.

Study the diagram given below and then answer the questions that follow:
(a) Identify the tissue and give a reason to support your answer.
(b) Name the parts labelled 1,2,3 and 4.
(c) Where is this tissue likely to be found in the plant?
(d) State the function of the parts labelled 1,2,3 and 4.

(a) The diagram given is a section of a phloem tissue in plants.

(b) The following parts are labelled:

1 – Sieve cell
2 – Phloem parenchyma cell
3 – companion cell
4 – sieve plate

(c) In plants, phloem is found in the stem and leaves as it is the tissue that conducts food, the manufactured food in the leaves needs to be transported to other plant parts.
(d) Listed below are the functions of the labelled parts:
1: Sieve cell – assists in transporting food from leaves to storage structures and other plant parts.
2: Phloem parenchyma cell – Stores fat, starch and other organic food material
3: companion cell – Facilitates the functioning of the cells of sieve tube
4: sieve plate – Dissolved organic solutes and water moves through these structures as it contains perforations

Write in brief about arrector pili muscle.

They are special muscles consisting of smooth muscle fibres. They remain attached between the epidermis and the hair follicle. Their contraction causes the raising of hair.

Differentiate between cells of:
Fibers of voluntary muscle and cardiac muscle

$$\begin{array}{|c|c|c|}\hline \text { Properties } & \text { Fibers Of Voluntary muscle } & \text { Fibers Of Cardiac muscle } \\\hline \text { Shape } & \text { Cylindrical and long } & \text { Branched and short } \\\hline \text { Nucleated } & \text { Multinucleated } & \text { Uninucleated } \\\hline \text { Nature } & \text { Under one's control } & \text { Not under one's control } \\\hline \text { Example } & \text { Legs, Arms, neck } & \text { Heart } \\\hline\end{array}$$

Name the following:
The tissue concerned with upward conduction of water in plants.

Xylem is the tissue concerned with upward conduction of water in plants.

Write the medical significance of Differential Leukocyte Count.

Medical Significance of differential leukocyte count:
$$\bullet$$ Any irregularity observed in the differential counting of the leucocytes is indicative of specific disease; further specialized testing can give a proper diagnosis of the disease and thus helps in proper treatment.
Some of these conditions are described below.

Nature of irregularity in differential leucocyte counting	Symptoms of possible diseases
Increase in the number of Neutrophils	Infection leading to normal pus, Sign of inflammation & dermatitis.
Increase in Eosinophils	Hypersensitivity or Allergy and signs of Parasitic infection
Increase in Basophils	Chickenpox disease
Increase in Lymphocytes	Whooping cough
Increase in Monocytes	Signs of Tuberculosis
The decrease in $$T_4$$ Lymphocytes	Signs of AIDS

(In General differential leukocyte count do not include $$T_4$$ lymphocytes).

Explain the role of ESR in disease diagnosis.

Value of ESR increases in many chronic diseases such as TB, Arthritis, Allergy etc. ESR value also increases during pregnancy, Anaemia and old age, in this way it helps in diagnosis of a disease.

What is the color and shape of white blood cells?

The color is white, and the shape is always changing. Thus they are irregular in shape.

Where RBC is formed?

RBC are formed in the Red bone marrow.

What is used for total leucocyte count?

Neubauer haemocytometer is used for total leukocyte count.

What is apothorax?

Apothorax is the region that contains the heart and the lungs. Thus it is the region that is supported by the ribcage, sternum and spine.

How many vertebrae make up the spinal cord?

In humans, the vertebral column is formed by 26 serially arranged vertebrae and is dorsally placed. The vertebral column is differentiated into cervical (7), thoracic (12), lumbar (5), sacral (1-fused) and coccygeal (1-fused) region.

Our body contains a large number of cells L which are the longest cells in the body. L has long and short branches called M and N respectively. There is a gap O between two L cells, through which nerve impulse transfer by the release of chemical substance P.
(i) Name the cells L
(ii) What are M and N?
(iii) What is the gap O?
(iv) Name the chemical substance P

(i) 'L' refers to neurons.

(ii) 'M' - Dendrites, 'N' - Axon

(iii) 'O' - Synapse

(iv) The chemical substance 'P' is acetylcholine

What is cartilage? Give two functions.

Cartilage is one of the connective tissue, that is compact, less vascular and very flexible. They are found in joints and discs between vertebrae. Functions of cartilage are:

(1)It provides support and flexibility to body parts.

(2) It smoothens surface at joints.

Mark the odd one in each series.
(a) Areolar tissue; blood; neuron; tendon
(b) RBC; WBC; platelets; cartilage
(c) Exocrine; endocrine; salivary gland; ligament
(d) Maxilla; mandible; labrum; antennae
(e) Protonema; mesothorax; metathorax; coxa

(a) Areolar tissue, blood, and tendons are examples of connective tissues. A neuron is an example of neural tissue.

(b) RBCs, WBCs, and platelets are the three most important components of blood (fluid connective tissue) while cartilage is skeletal connective tissue.

(c) Exocrine, endocrine, and salivary glands are examples of the simple glandular epithelium. The ligament is a connective tissue.

(d) Maxilla, mandible, and labrum are mouth parts of a cockroach; white antennae are present in the head constituent of the region of cockroaches.

(e) Prothorax, mesothorax and metathorax are parts of the thorax of cockroach and present in the legs of a cockroach. Protonema is usually a filamentous structure produced by the germination of the spore in mosses and certain related plants, and from which the leafy plant which bears the sexual organs arises as a lateral or terminal shoot.

Identify the type of tissue in the following: Skin, Bark of tree, Bone , Lining of kidney tubule, Vascular bundle.

1. Skin: Squamous epithelium (thin, flattened, irregularly shaped cells with centrally placed nucleus).

2. Bark of tree: Cork (protective tissue with dead suberized cells)

3. Bone: Skeletal tissue/osseous tissue

4. Lining of kidney tubule: Cuboidal epithelial tissue (cube like cells with hexagonal appearance and central, spherical nucleus).

5. Vascular bundle: xylem (tracheids, vessels, fibres and parenchyma) and phloem (sieve elements, companion cell, phloem fibres and phloem parenchyma )

Distinguish between cardiac muscle and striated muscle.

The muscles of the heart show rhythmic contraction and relaxation throughout life. These involuntary muscles are called cardiac muscles. Heart muscle cells are cylindrical, branched and uninucleate.

Voluntary muscles are also called skeletal muscles as they are mostly attached to bones and help in body movement. Under the microscope, these muscles show alternate light and dark bands or striations when stained appropriately. As a result, they are also called striated muscles. The cells of this tissue are long, cylindrical, unbranched and multinucleate (having many nuclei).

Name the following.

(a) Tissue that forms the inner lining of our mouth. (b) Tissue that connects muscle to bone in humans. (c) Tissue that transports food in plants. (d) Tissue that stores fat in our body. (e) Connective tissue with a fluid matrix. (f) Tissue present in the brain.

Answer:

a. Epithelial tissue is the tissue that makes up the inside lining of our mouth.

b. Tendons are the connective tissue that connects muscle to bone in humans.

c. Phloem is a type of plant tissue that delivers food.

d. Adipose tissue is the fat-storing tissue in our bodies.

e. Blood is a liquid connective tissue composed of a fluid matrix and blood cells.

f. Nervous tissue is a type of connective tissue found in the brain.

Classify the type of neurons and state their functions.

There are different types of neurons in the organisms which are responsible for performing specific functions. There are three types of neurons.

The sensory neuron conduct nervous impulses from the sense organs to the brain and spinal cord. They bring the information from the receptor organs.

There are motor neurons which carry impulses from the brain and spinal cord to the muscles and glands. They carry the messages to the effector organs.
There are association neurons which perform integrative functions of the nervous system. These are the neurons which conducts the impulse between two neurons and are called as interneurons.

Given below is a diagram of a smear of human blood. Study the same and answer the questions that follow:
a. Name the parts 1, 2, 3 and 4 indicated by guidelines.
b. Mention two structural differences between the parts labelled '1' and '2'.
c. What is the main function of the parts labelled 1, 2 and 3 respectively?
d. What is the life span of the part labelled '1'?
e. Name a soluble protein found in '4' which helps in the clotting of blood.

a) 1) Red blood corpuscles, 2) White blood corpuscles, 3) Platelets, 4) Blood plasma.
b) RBCs lack nucleus whereas, WBCs have a nucleus. RBC has a biconcave shape while the shape of WBC is irregular.
c) Functions:-

1) RBCs- Its main function is to carry oxygen from the lungs to the body tissues and also carry carbon dioxide as a waste product away from tissues to lungs. Haemoglobin protein in RBCs helps in carrying oxygen.

2) WBCs- Its main function is to fight infection by preventing the entry of foreign particles.
3) Platelets:- Its main function is to prevent bleeding by clotting blood.

d) The life span of RBC is 120 days.
e) Fibrinogen is the soluble plasma protein that helps in blood clotting.

Why xylem is a type of complex tissue?

$$\textbf{Solution:}$$

$$\bullet$$Complex tissues are made of more than one type of cells.

$$\bullet$$Xylem is a complex tissue as it is made up of four types of cells:

$$\bullet$$Tracheids

$$\bullet$$Vessels

$$\bullet$$Xylem parenchyma

$$\bullet$$Xylem fibres

Value-based questions.
Name the tissues where the following structure occurs:
Canaliculi

Canaliculi are present in bone. They are microscopic canals present between the lacunae of bone. The cytoplasmic processes of osteocytes radiate into these canaliculi.

The diagram below represents the simplified pathway of the circulation of blood. Study the same and answer the questions that follow:
Draw a diagram of the different blood cells as seen in a smear of human blood.

1448242_843813_ans_428ac2a097774745841b402c63c63a74.png

Study the diagram given and answer the questions that follow:
i. Identify the structure.
ii. Label parts 1 to 5
iii. What is the function of part labelled 1?

It is nerve cell or neuron.
1) dentrites, 2) soma or body, 3) nucleus, 4) myelin sheath, 5) axon terminal
Dentrites are branched protoplasmic extensions.
They help in the propagation of electrochemical stimulation to the soma.

Explain how does the exchange of gases occur in plants across the surface of stem, roots and leaves.

In all the three plant parts the exchange of gases takes place through diffusion.

However the surface of a young stem will have stomata, while that of an older stem will have lenticels. The stomatal apparatus consists of a pore called the stoma, a pair of guard cells and subsidiary cells surrounding them. The exchange of gases through the stomatal pore is dependent upon the turgidity of the guard cells. Stomata are mainly present on the surface of the leaves apart from the epidermal surface of young stem. Lenticels are open pores. In roots stomatal pores as well as lenticels are absent, exchange of gases occurs through root hairs.

"Skeletal and cardiac muscle fibres are striated in appearance" explain.

$$\textbf{Solution}$$

$$\bullet$$Striated muscles are the muscle tissues which have a repeating sequence of functional unit called sarcomeres.

$$\bullet$$ The presence of sarcomeres gives a series of band like structure which gives us striated appearance to the muscle tissues.
$$\bullet$$ Both cardiac and skeletal muscles appear striated because the cells of these muscles are arranged in bundles.
$$\bullet$$ Skeletal muscles the tissues are present in repetitive bands of actin and myosin due to which the cell appear to be banded.
$$\bullet$$ The cardiac muscle cells are branched and the contained discs which is why they appear striated.

Differentiate between skeletal muscles. smooth muscle, and cardiac muscle (at least two points in each)

1) Skeletal muscles: It is a form of striated muscle tissue, which is under the voluntary control of the somatic nervous system. Most skeletal muscles are attached to bones by bundles of collagen fibres known as tendons.

2) Smooth muscle: Smooth muscle generally forms the supporting tissue of blood vessels and hollow internal organs, such as the stomach, intestine, and bladder.

3) Cardiac muscle: The cardiac muscle function has a movement of contraction, which moves the blood into the heart and the circulatory system that goes throughout the body. The cardiac muscle function is important because it keeps the blood flowing within the heart so that it can continue to pump.

Group 'A'	Group 'B'
Heart beats	a. 350 ml
RBC	b. 7.4
WBC	c. $$37^oC$$
Blood Donation	d. 72
Normal body	e. 4-6 $$millions /mm^3$$
pH of oxygenated blood	f. 5000-6000 / $$mm^2$$

Column A	Column B
(a) Secretion and absorption	----
(b) Protective covering	----
(c) Linking and supporting framework	----

Tissues - Class 9 Biology - Extra Questions

State the different types of neurons. Explain their functions.

A tendon connects a .......... to a ..........

Differenciate between striated and unstriated muscles on the basis of their function and location in the body. Also compare their structure.

Human cheek cells stained and mounted in glycerine were observed with the help of a compound microscope. Name the stain used and name the components of the cell which would be seen:

Choose the ODD one out from the following terms given and name the CATEGORY to which the others belong.Example: Nose, Tongue, Arm, EyeAnswer: Odd Term- Arm, Category- Sense organsDendrites, Medullary Sheath, Axon, Spinal cord.

The basic structural unit of the nervous system is ...........................

Name the location of Nissl's granules

Name the site of exchange of material between the blood and the surrounding cells.

Short AnswerWhy are white blood cells called the soldiers of body ?

Unscramble the jumbled word.Isecsum

What is the function of Lymphocytes?

Name one place where the following tissue is located:Squamous epithelium

Answer the following:Name the major site where RBCs are formed.

The longest cell in animals.

Mention the components of the transport system in highly organized plants. State the functions of these components.

What is visceral muscle? Where is it found?

Why do we consider blood as a connective tissue?

What is the role of epidermis in plants?

Differentiate between striated, unstriated and cardiac muscles on the basis of their structure and site/location in the body.

Diagrammatically show the difference between the three types of muscle fibres.

What is the specific function of the cardiac muscle?

What are the functions of areolar tissue?

Name the following:(a) Primary functional unit of brin:(b) The small gap between the consecutive neurons:(c) Part of the brain that coordinates the voluntary functions:

Name the following :(i) The cell body of a nerve cell.(ii) The waxy layer on the epidermis of the leaf meant to reduce transpiration.(iii) A non-biodegradable pesticide.(iv) The physical expression of genes in an individual.(v) Knot-like mass of blood capillaries inside the bowman's capsule.

Give an account on cellular components of blood.

Draw a labelled diagram of the T.S. of bone

Explain the structure and function of neuron.

Explain the structure of neuron.

Draw the diagram of neuron and label any two parts.

State two functions of areolar tissue.

Find the odd one and also write down the common features of others.(a) Dendrite, Cell body, Axon, Nephron(b) Epilepsy, Parkinson's disease, Mumps, Alzheimer's disease(c) Melatonin, Insulin, Glucagon, Ethylene

Create a poster/flowchart to depict all that you have learnt in this chapter about plant tissues.

What are the two main types of nerves? Write their functions.

Fill in the blankRBC: Carrier of oxygen; WBC: ...............

Which blood cells are without nuclei? What is the advantage of this condition?

Write a note on erythrocytes.

What do you mean by fractured bone?

Why are fractured bones plastered?

What makes the blood look red?

What is cavity in bones?

Describe the structure of the multipolar neuron.

Neurons are packed around with some cells. What are these cells called?

Differentiate between :Myelinated and non-myelinated axons

Differentiate between :Dendrites and axons.

Name the components of the formed elements in the blood and mention one major function of each of them ?

Draw a labelled diagram of a neuron with a myelin sheath.

Given appropriate biological/ technical terms for the following:Cellular components of blood containing haemoglobin.

Write one word for each of the following :(a) A group of similar cells that perform specific function.(b) Least specialized cells in plants(c) Cells responsible for increase in diameter of the stem and root of dicot plants.

Name the three kinds of muscles in the human body giving one example of each.

Can you consider a cluster of eggs as a tissue? Why?

Short answerName the muscle found in the human heart?

Given is a diagram of a human blood smear. Study the diagram and answer the question that follows.Name the components numbered 1 to 4.

Give appropriate biological or technical terms for the following.Squeezing out of blood cells from the capillaries into the surrounding tissues.

What are bones made of ? Are the bones living or non-living ? Give reason.

What is the difference between ligament and tendon? What are their functions?

Define the term 'Tissue.'

Name different types of WBCs.

Name a simple living mechanical tissue.

Fill in the blanks with appropriate words.Root hairs are formed from extensions of the ..........

"Abnormally large number of WBC's in the blood are usually an indication of some infection in our body." Comment on the statement.

Name the tissue which connects muscle to a bone.

Very short answer type.What is a ligament?

Very short answer type.Mark the odd one in the given series.areolar tissue, blood, neuron, tendon

Very short answer type.How many types of muscles occur in the body of a vertebrate?

Differentiate between erythrocytes and leucocytes of mammals.

Which type of WBCs are called granulocytes and why?

Differentiate between.Hemopoiesis and hemolysis.

What are the characteristics of cardiac muscle? Describe its specific function.

Very short answer type.Mark the odd one in each series.neurolemma, dendrite, Z-band, myelin

Give two main differences between unstriped and striped muscular tissues and give examples of each.

Describe the structure and the functions of three types of muscular tissue

What roles do the dendrites, cell body, and axon play in communication of signals?

Name the kind of tissue that forms the inner lining of blood vessels.

Differentiate between.Neuron and nephron

Short/ Long answer type questions.Give four differences between red and white muscle fibres.

Give the other name for white bloods cells.

What is epidermis?

Describe briefly the structure of a nerve cell.

Give three features of cardiac muscles.

Choose the ODD one out from the following terms given and name the CATEGORY to which the others belong.
Example: Nose, Tongue, Arm, Eye
Answer: Odd Term- Arm, Category- Sense organs
Dendrites, Medullary Sheath, Axon, Spinal cord.

Short Answer
Why are white blood cells called the soldiers of body ?

Unscramble the jumbled word.
Isecsum

Name one place where the following tissue is located:
Squamous epithelium

Answer the following:
Name the major site where RBCs are formed.

Name the following:
(a) Primary functional unit of brin:
(b) The small gap between the consecutive neurons:
(c) Part of the brain that coordinates the voluntary functions:

Name the following :
(i) The cell body of a nerve cell.
(ii) The waxy layer on the epidermis of the leaf meant to reduce transpiration.
(iii) A non-biodegradable pesticide.
(iv) The physical expression of genes in an individual.
(v) Knot-like mass of blood capillaries inside the bowman's capsule.

Find the odd one and also write down the common features of others.
(a) Dendrite, Cell body, Axon, Nephron
(b) Epilepsy, Parkinson's disease, Mumps, Alzheimer's disease
(c) Melatonin, Insulin, Glucagon, Ethylene

Fill in the blank
RBC: Carrier of oxygen; WBC: ...............

Differentiate between :
Myelinated and non-myelinated axons

Differentiate between :
Dendrites and axons.

Given appropriate biological/ technical terms for the following:
Cellular components of blood containing haemoglobin.

Write one word for each of the following :
(a) A group of similar cells that perform specific function.
(b) Least specialized cells in plants
(c) Cells responsible for increase in diameter of the stem and root of dicot plants.

Short answer
Name the muscle found in the human heart?

Given is a diagram of a human blood smear. Study the diagram and answer the question that follows.
Name the components numbered 1 to 4.

Give appropriate biological or technical terms for the following.
Squeezing out of blood cells from the capillaries into the surrounding tissues.

Fill in the blanks with appropriate words.

Root hairs are formed from extensions of the ..........

Very short answer type.
What is a ligament?

Very short answer type.
Mark the odd one in the given series.
areolar tissue, blood, neuron, tendon

Very short answer type.
How many types of muscles occur in the body of a vertebrate?

Differentiate between.
Hemopoiesis and hemolysis.

Very short answer type.
Mark the odd one in each series.
neurolemma, dendrite, Z-band, myelin

Differentiate between.
Neuron and nephron

Short/ Long answer type questions.
Give four differences between red and white muscle fibres.

Describe the functions of the following components of the transport system.
(i) Blood
(ii) Lymph

I) What are the different types of muscular tissues?
ii) Write two differences between these tissues.
iii) What are unique characters of cardiac muscles?

Classify the following into cells, tissue, and organ.

skin, fat cell, RBC, blood, ear, muscle

Which one is largest and smallest
(a) Eosinophil
(b)Basophil
(c)Neutrophil
(d)Monocyte
(e) T-lymphocyte

Identify the odd word and explain why it is odd:
Cartilage, Bone, Tendon, Cardiac Muscle

Give reasons for this sentence:
A mature erythrocyte lacks nucleus and mitochondria.

Give reasons for the following
Leukocytes are called soldiers of our body.

Give one word for the following.
An iron containing protein present on the surface of red blood cells.

Write the function of the following.
Chordae tendineae.

The diagram given alongside is the external view of the human brain. Study the same and answer the question that follow.
What is the structural and functional unit of nervous system?

Give appropriate biological/technical terms for the following.
The tissue which stores fat.

Find out the correct matches:
Group 'A' Group 'B'
Heart beats a. 350 ml
RBC b. 7.4
WBC c. $$37^oC$$
Blood Donation d. 72
Normal body e. 4-6 $$millions /mm^3$$
pH of oxygenated blood f. 5000-6000 / $$mm^2$$

Name the following :
Tissue that connects muscle to bone in human.

Name the following:
Tissue that stores fat in our body.

Distiguish between the following pairs of terms:
Thrombocyte and Erythrocyte

Fill in the blanks.
Lining of blood vessels is made up of _____ tissue.

Write a short note.

Meristematic tissue.

The following statement is wrong. Rewrite it correctly by changing either one or two words.

Simple squamous epithelium is present in respiratory tract.