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CBSE Questions for Class 9 Biology Tissues Quiz 14 - MCQExams.com
CBSE
Class 9 Biology
Tissues
Quiz 14
Veins of leaves have both xylem and phloem
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True
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False
Explanation
True.
Veins of the leaves contain conjoint and colateral vascular bundles, hence contain both xylem and phloem.
Which statements describe functions of the backbone? Check all that applies to it.
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It supports the body’s weight
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It helps to break down food
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It surrounds and protects the brain
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It replaces the spinal cord in vertebrates
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It allows flexibility and movement
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It helps regulates water balance
At high altitude, Red blood cells
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Increase in number
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increase in size
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decrease in size
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Decrease in the number
Explanation
At high altitudes, the number of RBCs increases to compensate for the decrease in the level of atmospheric Oxygen.
Choose the correct option for the statements given below.
Statement 1 - An osteon consists of a Haversian canal surrounded by concentric lamellae that are interspersed by lacunae containing the osteocytes.
Statement 2 - The spongy bones in Mammals do not contain the osteon.
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Both statements are incorrect.
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Both statements are correct and statement 2 is the correct explanation of statement 1.
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Both statements are correct but statement 2 is not the correct explanation of statement 1.
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Statement 1 is correct but statement 2 is incorrect.
Explanation
The bone has a deposition of hard ground substance rich in calcium salts and collagen fibres.
A Haversian system or the osteon comprises of a Haversian canal that runs along the length of the bone. It encloses bloods vessels and nervous tissue. The Haversian canal is surrounded by the bone matrix which is arranged in the form of concentric rings. The rings are interspersed by cavity or lacunae that contain osteocytes. Two Haversian systems are connected by a Volkmann's canal transversely.
Both Haversian system and Volkmann's canal are absent in in the spongy bone and it is internally made up of trabeculae.
So, the correct answer is '
Both statements are correct but statement 2 is not the correct explanation of statement 1.'
The myelin sheath provides ......... to the axon.
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Mechanical support
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Electrical insulation
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Both A and B
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None of the above
Explanation
The myelin sheath of a neuron consists of fat-containing cells that insulate the axon from electrical activity. This insulation helps to increase the rate of transmission of signals. Myelin is made up of inter-twining hydrocarbon chains of sphingomyelin, which serve to strengthen the myelin sheath. Hence it also provides mechanical support to the neuron.
Thus the correct option is C.
Which of the following cells cannot be grown under tissue culture conditions?
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Hela cells
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Leucocytes
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Kidney cells
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Nerve cells
Explanation
Tissue culture is the culture of cells in in vitro conditions. Many types of cells can be grown through tissue culture in a culture medium.
A. HeLa is an immortal cell line used in scientific research. It is the oldest and most commonly used human cell line.
B. Leucocytes or the white blood cells can be cultured in a culture medium.
C. Kidney cells can also be cultured in a culture medium.
D. The culture of neuronal cells is particularly challenging since mature neurons do not undergo cell division.
Hence, nerve cells cannot be grown under tissue culture conditions.
So, the correct answer is 'Nerve cells'.
Nissl granules are found in cyton of nerve cells. These have affinity for basic dyes.
The granules are made up of
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Mitochondria
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Cell metabolites
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Fat granules
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Ribosomes
Explanation
Nissl granule is a large granular body found in neurons. It consists of rough endoplasmic reticulum and clusters of free ribosomes and are a site of protein synthesis. It was named after Franz Nissl, a German psychiatrist, who invented the Nissl staining method.
Thus, the correct answer is option (D), 'Ribosomes'.
The type of connective tissue that is associated with the umbilical cord is
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Areolar connective tissue
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Jelly-like connective tissue
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Adipose connective tissue
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Reticular connective tissue
Explanation
The intracellular mucoid connective tissue of the umbilical cord is called the Wharton's jelly. So, the tissue that is associated with umbilical cord is jelly-like in nature. It provides support for the veins and arteries of the umbilical chord. It is a clear jelly like substance which collapses when taken out from the mother's body.
Thus, the correct answer is option B.
Which of the following muscles gets fatigued very soon?
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Skeletal muscle
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Smooth muscle
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Cardiac muscle
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All of the above
Explanation
Muscle fatigue refers to a decrease in muscle force generated over time.
Skeletal muscles are used to
move the bones in the body
and may get fatigued because of overexertion.
Overexertion such as intensive exercise
results in depletion of oxygen levels in the muscles. So, the muscles shift temporarily to anaerobic metabolism to generate energy. This is done by the formation of lactic acid and energy. Accumulation of lactic acid in muscles leads to muscle fatigue.
The cardiac muscles are resistant to fatigue as
they contain large numbers of mitochondria (powerhouses of the cell), enabling continuous aerobic respiration and ATP production required for mechanical muscle contraction. The rate of contraction and relaxation in smooth muscles is very slow which consumes less ATP. Thus, smooth muscles also do not experience fatigue.
So, the correct answer is option A.
Ciliary muscles are contractile structures which
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Move cilia of some protozoans
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Keep valves of heart intact
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Change focal length of human eye and are found at junction of sclera and iris
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Cause erection of human hairs in cold and are situated in skin
Explanation
The ciliary muscle is a circular muscle that relaxes or tightens the zonules to enable the lens to change shape for focusing. It is present between the sclera (white of the eye) and the fine ligaments, that suspend the lens. It is composed of both longitudinal and circular fibres and serves to change the shape of the lens, enabling the eye to focus on near or distant objects.
Thus, the correct answer is option C.
Which one of the following is a matching pair of a certain body feature and its value/count in a normal human adult.
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Urea 5-10 mg/100ml of blood
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Blood sugar 80-100 mg/ 100 ml
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Total blood volume 3-4 litres
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ESR in Wintrobe method 9-15 mm per hour in males and 20-34 mm per hour in females
Explanation
B. Blood sugar 80-100 mg/100 ml
EXPLANATION: For the majority of human, normal blood sugar level is between 80-100 mg/ 100 ml. The blood sugar level after 1-2 hours of eating is less than 140 mg/ 100 ml. Before meal the level of blood sugar is less than 100 mg/ 100 ml.
Hence the correct option is B.
In the diagram of multipolar myelinated neuron given above, different parts have been indicated by alphabets. Choose the answers in which these alphabets have been correctly matched with the parts, which they indicate.
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A- Cell body, B- Nissl bodies, C- Nucleus, D- Dendrites, E- Naked portion of axon, F- Myelin sheath, G- Node of Ranvier
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A- Cell body, B- Nissl bodies, C- Naked portion of axon, D- Dendrites, E- Nucleus, F- Myelin sheath, G- Node of Ranvier
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A- Cell body, B- Nissl bodies, C- Naked portion of axon, D- Nucleus, E- Dendrites, F- Myelin sheath, G- Node of Ranvier
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A- Cell body, B- Nissl bodies, C- Dendrites, D- Nucleus, E- Naked portion of axon, F- Myelin sheath, G- Node of Ranvier
Explanation
A neuron is a structural and functional unit of the nervous tissue. It develops from the ectoderm of the embryo. The special properties of the nervous tissue are excitability and conductivity. A neuron consists of the main cell body and cytoplasmic processes arising from it. Neurons consist of the cell body, Nissl bodies, Dendrites, Node of Ranvier, Nucleus, a naked portion of an axon, Myelin sheath.
The option in which the parts are correctly matched with the alphabets is D.
The cell/s present in the meshwork of areolar tissue is/are
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Fibroblasts
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Macrophages
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Mast cells
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All of the above
Explanation
Areolar tissue is a connective tissue that takes part in the structural framework of the body. It consists of a meshwork of collagen, elastic fibers and reticular fibers with many connective tissue cells in between the meshwork of fibers. Fibroblasts, mast cells, and macrophages are the major cells of the areolar tissue. So, the correct answer is option D.
Read the statements regarding muscle proteins. Which of the following statement is correct?
(A) Actin is a thin filament and is made up of two F-actins.
(B) The complex protein, tropomyosin is distributed at regular intervals on the troponin.
(C) Myosin is a thick filament, which is also a polymerised protein.
D) The globular head of meromyosin consists of light meromyosin (LMM).
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(A), (B) and (C) are correct
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(A), (B) and (D) are correct
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(A) and (C) are correct
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(B) and (D) are correct
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(B), (C) and (D) are correct
Explanation
Sarcomere forms the structural and functional unit of striated muscle fibre. Each sarcomere is a bundle of fine longitudinal myofilaments of two types:
1. Primary myofilaments: They are thickened, confined to A- band only and free at both the ends. These are formed of protein myosin. Each myosin is a polymerised protein made of many monomeric proteins called meromyosin. Each meromyosin has two important parts- a globular head with a short arm and a tail, the former is called heavy meromyosin (HMM) and the latter is called (LMM).
2. Secondary myofilaments: They are thinner, occur in I-band only but extend for some distance into A-band. They are composed of protein actin having with it two regulatory proteins: tropomyosin and troponin and are attached to Z-lines on one end and are free at the other. Each actin filament is a polymerised protein made up of two 'F' (fibrous) actin strands helically wound to each other. Each 'F' actin is a polymer of monomeric 'G' (globular) actins. Two filaments of tropomyosin proteins also run along the length of 'F' actins. Also. a complex troponin protein of three globular peptides is distributed at regular intervals on the tropomyosin.
Thus, the correct answer is option C.
Mineral which helps in formation of RBCs is
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Fe (iron)
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Mn (manganese)
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Mg (magnesium)
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K (potassium)
Explanation
A mineral which helps in the formation of RBCs is iron (Fe) because i
ron makes up the active part of
haemoglobin which
directly binds to and carries oxygen. If we don’t eat enough iron, we cannot produce enough
haemoglobin
to make functional red blood cells. Hence the correct option is A.
Which one of the following is not a true cell?
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Monocytes
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Eosinophils
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Neutrophils
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Platelets
Explanation
Monocytes are the largest of all leukocytes and form a part of the innate immune system. They
have bean-shaped nuclei.
Red blood corpuscles or erythrocytes, rich in haemoglobin carry oxygen to different tissues. They lack nucleus at maturity.
Neutrophils are phagocytic leukocytes contributing to innate immunity. They have
a nucleus divided into 25 lobes.
Platelets are devoid of the nucleus. T
hey are fragments of cytoplasm which are derived from the megakaryocyte
of the bone marrow. Hence they are not considered as true cells.
Hence, the answer is (D) Platelets.
Fibrinogen is absent in
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Blood
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Serum
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Plasma
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Both B and C
Explanation
Fibrinogen is a glycoprotein present in the blood, which is involved in blood clot formation.
Blood consists of plasma, red blood cells, white blood cells, and platelets.
The serum is blood plasma without blood clotting factors like fibrinogen.
Plasma is a pale yellow-colored fluid that remains after red blood cells, white blood cells, and platelets are removed. Plasma contains the clotting factors like fibrinogen.
Thus, the correct answer is option B.
Intercalated disc is present in___________________.
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Striated muscle
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Smooth muscle
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Cardiac muscle
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Both A and C
Explanation
Cardiac muscles consist of cylindrical, branched and uninucleate myocytes which are interconnected by intercalated discs. Intercalated discs are cross-bands that separate the opposite ends of myocytes. They help to hold the adjacent cells together and transmit the force of contraction from cell to cell. These discs allow diffusion of ions across the cells due to which muscle impulses travel rapidly from cell to cell. Therefore, option C is correct.
Match the column (A) with the column (B).
Column A
Column B
A
Fluid connective tissue
1
Subcutaneous layer
B
Filling of space inside the organs
2
Cartilage
C
Striated muscle
3
Skeletal muscle
D
Adipose tissue
4
Areolar tissue
E
Surface of joints
5
Blood
F
Stratified squamous epithelium
6
Skin
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A- 5, B- 4, C- 3, D- 1, E- 2, F- 6
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A- 5, B- 6, C- 3, D- 1, E- 2, F- 4
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A- 5, B- 4, C- 1, D- 3, E- 2, F- 6
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A- 5, B- 4, C- 3, D- 1, E- 6, F- 2
Explanation
Blood
is a fluid connective tissue, which has plasma (liquid) as its matrix and red blood cells (RBC), white blood cells (WBC), platelets as cells.
Areolar tissue
is found in between skin and muscles, around blood vessels, neurons, and also in the bone marrow. Being soft and loose they carry out the function of supporting internal organs and repairing of tissues by filling spaces.
Striated muscle
tissues are tissues, which have pattern of repeating sarcomere. A sarcomere is the basic unit of muscle. Striated skeletal muscle tissues are attached to bones and are voluntarily controlled, i.e., controlled by will.
Adipose tissue
is a type of connective tissue in which fat is stored. They are generally located below the skin. The layer of adipose tissue beneath the skin is known as the subcutaneous layer, which acts as an insulator.
Cartilage
is a type of connective tissue in which solid matrix is made of protein and sugars. Cartilage is present on the joint surface and makes it smooth.
Squamous epithelium
cells are thin and flat and form a delicate lining. In skin squamous epithelium cells are arranged in many layers hence, called stratified squamous epithelium. It protects the body.
So, the correct answer is option A.
Which is the correct match?
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Dendrite - Accepts signal / stimulus
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Dendrite - Sends signal / stimulus
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Axon - Smallest part of neuron
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Synaptic knob - Present at the end of dendron
Explanation
The dendrites accept signals generated by other neurons. These signals may be excitatory or inhibitory. All signals present at the dendrites of a neuron are combined and the result will determine whether or not that neuron will fire. If a neuron fires, an electrical impulse is generated.
An axon, or nerve fibre, is a long slender projection of a nerve cell or neuron, that conducts electrical impulses away from the neuron's cell body or soma.
Axon terminals have knob-like swellings at the very end called synaptic knobs. The function of a synaptic knob is to change the action potential that is carried by axons into a chemical message.
Therefore, the correct answer is option A.
If you observe the muscular tissue of urinary bladder, you will observe
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Striated muscle
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Unstriated muscle
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Ligament
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Tendon
Explanation
Contraction or relaxation of the urinary bladder is involuntary movement. When urine is formed, it is stored in the urinary bladder and its muscles are stretched. After accumulation of a certain amount of urine volume, urge of voiding is felt, as the stretched muscle send the signal to the brain. Involuntary muscles are unstriated or smooth muscles. Therefore, the correct answer is option B.
Blood cells which show phagocytosis are
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Platelets
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Eosinophils
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Basophils
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Monocytes
Explanation
Platelets are the colourless blood cells, which form the blood clot. It stops bleeding by forming plugs in blood vessel injuries.
Eosinophils are a type of white blood cells, which are involved in various immune reactions.
A basophil is a granulocyte, which is involved in allergic reactions.
Monocyte is a type of white blood cell. Monocytes move quickly to the site of infection and divide to macrophages, which then carry out phagocytosis of foreign material
.
Therefore, option D is correct.
Which of the following is the function of epithelial tissue?
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Protection
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Secretion
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Absorption
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All of the above
Explanation
Epithelial tissue covers almost all organs and cavities in the body. The whole body is covered with skin which is a type of epithelial tissue. Skin shows layers of squamous epithelium.
Such layer provides protection to the skin from wear and tear and also provides protection from pathogen invasion. In stomach, absorption and secretion takes place. Here, epithelial cell structure is changed and columnar cells formed. Therefore, option D is correct.
Which one of the following mammalian cells is not capable of metabolizing glucose to carbon dioxide aerobically ?
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Red blood cells
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White blood cells
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Unstriated muscle cells
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Liver cells
Explanation
RBCs of mammalian cells at maturity lose all the organelles and the space is replaced by haemoglobin. So it does not contain mitochondria and the oxidative enzymes of mitochondria to carry out the Krebs cycle. It instead uses EMP and hexose monophosphate shunt to anaerobically breakdown glucose to release ATP
So, the correct answer is '
Red blood cells'
The epidermis and rootcap are produced by
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Dermatogen
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Periblem
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Plerome
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Calyptrogen
Explanation
The epidermis and root cap are produced by dermatogen. The protoderm forms periblem, plerom, and dermatogen.
Thus, the correct answer is option A.
Striated muscles are found as fasciculi, which are surrounded by
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Perimysium
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Epimysium
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Endomysium
0%
None of the above
Explanation
Skeletal muscles are usually attached to bone by tendons that are composed of connective tissue. This connective tissue also ensheaths the entire muscle and is called as epimysium. Skeletal muscles contain numerous subunits or bundles called fascicles (or fascicles). These fascicles are also surrounded by connective tissue (called the as perimysium) and each fascicle is composed of numerous muscle fibers (or muscle cells).
Thus, the correct answer is option A.
Which one of the following muscles is responsible for moving and shaking the skin?
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Arrector pilli
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Collagen fibres
0%
Panniculus carnosus
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Sphincter muscles
Explanation
The panniculus carnosus is a sheath of dermal (skin) muscle, developed in many mammals, that allows the movement of the skin independent of the movement of deeper muscle masses. In humans, the platysma muscle of the neck, palmaris brevis in the hand and the dartos muscle in the scrotum are described as a discrete muscle of the panniculus carnosus.
Hence the correct option is C.
Helper T-lymphocytes are characterised to release .................
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Serotonin
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Histamine
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Pyrogenes
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Cytokines
Explanation
Cytokines are secreted by helper T-cells in response to stimulation by antigens and acts on other cells of the immune system, thereby activating them. Serotonin and histamines are produced by mast cells whereas pyrogens are endotoxins.
Thus, the correct answer is option (D).
A man was infested with germs and was taken to the hospital. On pathological tests, it was found that he had
a. A low number of RBC
b. A high number of WBC and a low number of RBC
c. A low number of WBC
d. A high number of platelets
Which of the following alternative is correct?
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b only
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a and d
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c only
0%
d only
Explanation
White blood cells (WBCs) are cells of the immune system involved in defending the body against both infectious diseases and foreign materials. Therefore, an abnormally high of WBC may agree with the suspicion that an infection is present and the doctor will order further tests.
An abnormally low level of RBC may signal to the physician that the patient may be suffering from anemia, which might have caused by any intestinal worm infestation, like Hookworm.
Although total WBC count falls in viral infections, viruses are not considered as germs, which have infected the subject (man).
Bacterial or viral infections are the most common causes of a high white blood cell count. The increase in white blood cells due to infection is caused by a normal response of the immune system triggering the bone marrow to release additional stored white blood cells into the blood to fight off the disease. Low level of RBC may result in reduced immunity.
Hence A is the correct option.
The RBCs of the camel are:
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Circular, convex and non-nucleated
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Circular, convex and nucleated
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Oval and non-nucleated
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Oval and nucleated
Explanation
The red blood cells of camel are oval-shaped and they also have a nucleus in them, unlike in other mammals, where the RBCs are circular and enucleated. The oval shape helps to facilitate their flow in a dehydrated state. These cells are also more stable in order to withstand high osmotic variation without rupturing when drinking large amounts of water. Thus, the correct answer is option D.
Eleidin proteins are found in the layer of mammalian skin, stratum
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Germinativum
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Lucidum
0%
Granulosum
0%
Corneum
Explanation
Eleidin is a clear intracellular protein, which is present in the stratum lucidum of the skin. Eleidin is a transformation product of the amino acid complex keratohyalin.
Thus, the correct answer is option (B), 'Lucidum'.
Fatty substance found in epidermal cell walls is
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Cutin
0%
Suberin
0%
Both A and B
0%
Wax
Explanation
The cuticle is the waxy layer present on the epidermis of the leaf and it reduces the rate of water loss by transpiration in certain higher plants.
It consists of cutin, a waxy, water-repellent substance allied to suberin, which is found in the cell walls of corky tissue.
Cutin is especially noticeable in many fruits, e.g., apple, nectarine, and cherry, which can be buffed to a high gloss.
Carnauba
wax is derived from the cuticles of the leaves of
Copernicia cerifera
, a Brazilian palm.
Thus, the correct answer is option A.
How many tissue systems are suggested by Sachs?
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Two
0%
Three
0%
Four
0%
Five
Explanation
Two or more tissues together constitutes the tissue system. The activities of the constituent tissues are responsible for the major functioning, although they are different in structure and origin. All the different type of tissues in a plant that perform the similar basic function, irrespective of their location is known as tissue system.
Sachs (1875), recognized three types of tissue system in plants:
1. Epidermal or Dermal Tissue System
2. Cortical or Fundamental or Ground Tissue System.
3. Vascular Tissue System.
So, the correct answer is '
Three'
Tissue which connects skin with underlying muscle is made up of:
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Epithelial tissue
0%
Blood
0%
Adipose tissue
0%
Areolar connective tissue
Explanation
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 the repair of tissues.
Hence, the correct option is D.
Which of the following
sclereids are the
characteristic of intercellular spaces of
Nymphaea?
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Osteosclereids
0%
Brachysclereids
0%
Macrosclereids
0%
Astrosclereids
Explanation
Astrosclereids are sclereids having cell wall drawn out into lobes or arms to form a more or less stellate body. They are found in certain xerophytes.
Nymphaea
contains large intercellular spaces, which occur in the petiole. These airspaces are surrounded by long columns of parenchyma cells. The columnar cells contain chloroplasts and are presumably photosynthetic. Part of a large astroscleried can be seen cutting across one of the parenchymatous fingers. These sclereids add some mechanical strength to fragile structure.
Hence the option is D
Pigmented dendritic cells occur in
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Stratum Malpighii
0%
Stratum granulosum
0%
Stratum corneum
0%
Stratum lucidum
Explanation
Epidermis is the outer part of skin, which is keratinised and composed of stratified squamous epithelium layers. In the structure of epidermis on the basis of shape of cells and cytoplasm, there are five stratum -
(1) Stratum Malpighii
(2) Stratum spinosum
(3) Stratum granulosum
(4) Stratum lucidum
(5) Stratum corneum
An innermost stratum of epidermis consisting of one layer of cells is called as stratum Malpighii. It is also called as stratum basale. Cells are cubical or columnar in shape. In this stratum two types of cells are present.
(i) Melanocytes - They are called pigmented dendritic cell. These cells are formed by modification of cell which lies at the junction of epidermis and dermis.
(ii) Keratinocytes - They get their nutrition from underlying connective tissue of dermis and divide to form another stratum of the epidermis.
In grasses, certain adaxial epidermal cells along the veins modify themselves into large empty, colourless cells. These cells are called
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Bulliform cells
0%
Companion cells
0%
Guard cells
0%
Subsidiary cells
0%
Albuminous cells
Explanation
Bulliform cells are so called because of its peculiar bubble shape. It mainly occurs on the upper surface of the leaves present in grasses. Water present in these cells helps to maintain its shape but loss of turgor pressure during the stress allows the leaves to roll up. During drought, the loss of moisture through vacuoles induces bulliform cells to cause the leaves of many grass species to close as the two edges of the grass blade fold up toward each other. Once adequate water is available, these cells enlarge and the leaves open again.
Companion cells are specialized parenchyma cell, located in the phloem of flowering plants and closely associated with development and function with a sieve-tube element.
Guard cells are cells surrounding each stoma. They help to regulate the rate of transpiration by opening and closing the stomata.
The stoma is protected by subsidiary cells that have papillae that arch across the stoma, creating a mini-depression. This will tend to retain escaped water, giving it time to diffuse back into the stoma instead of being immediately blown away by a breeze.
Albuminous cells have a similar role to companion cells, but are associated with sieve cells only and are therefore found only in seedless vascular plants and gymnosperms.
So, the correct answer is option A.
When subminimal stimulus is given, then
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Muscles contract vigorously
0%
Muscles contract slowly
0%
Muscles never contract
0%
Muscles become fatigued
Explanation
Muscles are excitatory tissue. Muscle contraction is initiated by a signal sent by the central nervous system (CNS) via a motor neuron. A motor neuron along with the muscle fibres connected to it constitute a motor unit. The junction between a motor neuron and the sarcolemma of the muscle fibre is called the neuromuscular junction or motor-end plate. A neural signal reaching this junction releases a neurotransmitter (Acetylcholine) which generates an action potential in the sarcolemma. This spreads through the muscle
fibre and causes the release of calcium ions into the sarcoplasm. The muscle fibres contract based on all or none philosophy and the nervous stimulus should be above a critical threshold to cause muscular contraction. In case the stimulus is sub-minimal, muscles will not contract. This is called All or None law.
Hence the correct option is C.
Periblem forms
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Endodermis
0%
Cortex
0%
Both A and B
0%
Epidermis
Explanation
Histogen theory (By Hanstein 1870) states that shoot apical meristem consists three distinct zones :
Dermatogen (external layer) forms the outer covering of all organ of the plant.
Periblem (middle layer) gives rise to the cortex and endodermis.
Plerome (central layer) forms pith and primary vascular bundle.
Thus, option C is correct.
Blood differs from the other connective tissues because
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Plasma of blood is not entirely secreted by blood cells
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Blood corpuscles are not formed in the blood
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Fibres are absent in the blood
0%
All of the above
Explanation
$$\textbf{Correct option:}$$
$$\textbf{(D)}$$
$$\textbf{Solution:}$$
$$\textbf{Option (A):}$$
$$\bullet$$ Plasma of blood is the liquid or fluid part of the blood which constitutes around 92% water and 8% plasma.
$$\bullet$$ Plasma is secreted or produced in the liver and not secreted by the blood cell.
$$\textbf{Option (B):}$$
$$\bullet$$ Blood corpuscles or blood cells includes red blood cell, white blood cell, platelets that are formed in the bone marrow not in the blood through a process called hematopoiesis.
$$\bullet$$ RBC helps in the transport of oxygen to all the other parts of the body, WBC provides immunity against various pathogen and disease-causing organism, platelets prevents bleeding.
$$\textbf{Option (C):}$$
$$\bullet$$ Fibres are absent in blood but found in the connective tissue.
Hence, the correct option is (D).
The term periderm is used to denote
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Cortex
0%
Secondary cortex
0%
Both A and B
0%
None of the above
Explanation
The periderm is the secondary protective dermal tissue that replaces the epidermis during growth in thickness of stems and roots of gymnosperms and dicotyledons i.e., secondary growth.
Unlike typical epidermis, the periderm is a multilayered tissue system, the bulk of which usually constitutes the cork or phellem. It also has secondary cortex.
Hence the correct option is C.
Phosphagen in vertebrates is:
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0%
Phospho creatine
0%
Phospho arginine
0%
ATP
0%
Phosphoric acid
Explanation
The phosphagens are energy storage compounds, also known as high-energy phosphate compounds. They are chiefly found in muscular tissue in animals. ATP molecules can provide energy for only a few seconds of strenuous muscular activity. Thus muscle cells have backup energy storage compound, creatine phosphate, that can be stockpiled. The energy stored in creatine phosphate is transferred to ATP as needed. But during vigorous exercise, the supply of creatine phosphate is quickly depleted. Muscle cells must replenish their supplies of these energy-rich compounds. Chemical energy is stored in muscle fibers as glycogen, a large polysaccharide formed from hundreds of glucose molecules. Glycogen can be degraded, yielding glucose, which is then degraded in cellular respiration. When sufficient oxygen is available, enough energy is captured from glucose to produce needed quantities of ATP and creatine phosphate.
Hence the correct option is A.
Nissl granules are mostly present in
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0%
Axon
0%
Cyton
0%
Dendron
0%
Schwann cells
Explanation
A Nissl body is a large granular body found in neurons. These granules are rough endoplasmic reticulum (RER) with rosettes of free ribosomes and are the site of protein synthesis. These are present in cyton of the nerve cell.
So, the correct answer is option B.
In a leaf, vascular bundles are found in:
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0%
Veins
0%
Palisade tissue
0%
Lamina
0%
Lower epidermis
Explanation
Vascular
bundles are a collection of tube-like tissues that flow through plants, transporting various substances to various parts of
the
plant.
The vascular tissue present in vascular bundles exists in two forms: xylem and phloem. In leaves, these are generally present in the veins where the xylem channelizes the water and phloem conducts the prepared food.
Thus, the correct answer is option A.
The wax like substance present in the cell wall of onion skin is
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0%
Pectin
0%
Lignin
0%
Cellulose
0%
Suberin
Explanation
Onion epidermal skin forms a protective layer against harmful viruses and fungi which can infect underlying soft, sensitive tissues. One of the protective mechanism in onion is the presence of suberin in onion cell wall. The cell wall of onion becomes thick and waterproof due to deposition of suberin. Therefore, option D is correct.
Choose the correctly matched pair.
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0%
Tendon - Specialized connective tissue
0%
Adipose tissue - Dense connective tissue
0%
Areolar tissue - Loose connective tissue
0%
Cartilage - Loose connective tissue
Explanation
Loose connective tissue is a category of connective tissue, which includes areolar tissue, reticular tissue, and adipose tissue.
A tendon is a fibrous connective tissue, which attaches muscle to bone.
Cartilage is a skeletal connective tissue in animals and is found in the joints between bones, the rib cage, the ear, the nose, the bronchial tubes.
So, the correct answer is option C.
A bone left in dilute HCl for about three days will______________
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0%
Crack into pieces
0%
Become soft and elastic
0%
Dissolve completely
0%
Remain as it is
Explanation
HCl is hydrochloric acid, strong acid. Bone is made of minerals, and the most prominent mineral is calcium. When a bone is dropped in the HCl medium, the calcium of bone slowly starts dissolve due to the action of the strong acid. HCl + Ca -> CaCl$$_2$$ + H$$_2$$. Afterward, the bone is depleted of calcium but it does not "melt" because there are other minerals that make up the bone such as potassium, vitamins, and collagen. Since calcium is the main mineral in the bone, the bone becomes brittle and more susceptible to breakage. Therefore, the correct answer is option B.
A mature human erythrocyte has the typical characteristic of
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0%
A eukaryotic cell
0%
A prokaryotic cell
0%
Both eukaryotic and prokaryotic cell
0%
Neither eukaryotic nor prokaryotic cell
Explanation
Mature human erythrocytes are eukaryotic cells, which have lost their nucleus and organelles. Initially, the RBCs have nucleus but lose it with maturation. Prokaryotic cells include bacteria and archaea bacteria. Prokaryotes are exclusively unicellular with a naked DNA, while erythrocytes (RBCs) are part of a multicellular organism. All eukaryotic cell has a nucleus, but RBC doesn't. So, they have properties of neither prokaryotes nor eukaryotes.
Which of the following muscles are striated and branched?
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0%
Skeletal muscles
0%
Smooth muscles
0%
Cardiac muscles
0%
Both A and C
Explanation
The cardiac muscles (heart muscles) are involuntary striated muscles that are found in the walls of the heart. The heart is a pumping organ that needs to work tirelessly. To ensure this pumping efficiently, the c
ardiac muscle cells are bundled together giving the muscle a branched appearance. These bundled cells thus allow quick transmission of electrical signals which aid in efficient contraction and relaxation of the cardiac muscles. This in turn helps in the efficient pumping of the heart.
So, the correct answer is option C.
The above flow chart shows the three steps of glucose breakdown in different conditions. Which of the given steps is responsible for muscle cramps?
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0%
Step I
0%
Step II
0%
Step III
0%
Both (A) and (B)
Explanation
Lactate is formed from the breakdown of glucose during anaerobic respiration.
The cells make ATP during this process, which provides energy for most of the chemical reactions in the body. Lactate formation doesn't use oxygen, hence the process is often called anaerobic metabolism. Lactate-related ATP production is very fast. This makes it ideal for satisfying energy needs anytime exercise intensity exceeds 50% of maximum capacity.
However the accumulation of lactic acid leads to muscle fatigue and muscle cramps.
Hence the correct option is B.
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Practice Class 9 Biology Quiz Questions and Answers
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