Body Fluids And Circulation - Class 11 Medical Biology - Extra Questions

Short / Long type answer type questions.
The heart rates of an elephant, a human and a mouse are nearly 25, 72 and more than 200 per minute respectively (I) what conclusion can you draw from these observations? (ii) What is the significance of this difference in the heart rates?

1. Animals with larger size like elephants have a slow heart rate than the small organisms like mouse. 
2. This is significant for efficient metabolism. The body heat of small-sized animals is rapidly emitted. As a result, it has to burn more calories to maintain the body temperature at a normal level. This requires more oxygen. And to deliver oxygen to the body cells, the animal's heart need to be beat more faster.


Short / Long type answer type questions.
Fluids are injected into the circulatory system through the veins and not arteries.

Fluids are injected into the circulatory system through the veins and not arteries because :
1. Arteries are deep, Veins are superficial so easy to access.
2. Arteries have higher pressures, so puncture site more likely to bleed if pressure not applied till bleeding stops.
3. There is usually only one artery supplying a limb (where it is easier to access) but more than one veins draining the same areas.


Define open and closed circulatory system.

In open circulatory system, the blood vessels open into spaces and not into capillaries, so that blood comes in direct contact with tissues. Whereas in closed circulatory system, blood flows through capillaries connected by arteries and veins.
In open circulatory system, the rate of circulation is slow whereas it is rapid in closed circulatory system.


Who discovered the circulation of blood in closed circulatory system?

Realdo Columbo discovered that the heart's four valves permitted flow of blood in one direction only: from the right ventricle to the lungs, back to the left ventricle, and from there to the aorta. Realdo Columbo was lived in between 1515–1559 and on vivsection he confirmed the pulmonary circulation William Harvey was born on 1 April 1578.



Human heart is myogenic, yet a parasympathetic nerve can reduce the heart rate. Name the nerve.

The heart is influenced by the autonomic nerves originating from the cardiac centre from the medulla oblongata and reach here through the autonomic nervous system. These are parasympathetic and sympathetic nerves. They are antagonistic to one another. The vagus nerves (parasympathetic) supply mainly the SA and AV node and atrial muscle. Parasympathetic stimulation reduces the rate at which impulses are produced, decreasing the rate and force of the heartbeat. 


What is the role of folowing: (i) Lymph (ii) RBCs?

a. Lymph- It is a straw colored fluid present in the interstitial space. It flows through lymphatic vessels that ultimately joins the veins. It contains WBCs or leucocytes. 
Therefore, it helps maintaining water balance in the interstitial space.
Fights invading micro-organisms.
Removes wastes produced by the cells.
Absorbs digested fats from the intestine, through specialized lymph vessels called lacteals.
b. RBC's-Red blood cells contains haemoglobin that transports oxygen from the lungs  to cells of the body.


Describe the flow of blood through the heart of human beings.

Deoxygenated blood from different organs comes to the right atrium through the vena cava.
From the right atrium, blood goes to the right ventricle. The tricuspid valve between the right atrium and right ventricle prevents the backflow of blood.
From the right ventricle. blood goes to the lungs through pulmonary artery. Inside the lungs, carbon dioxide is removed from the blood and oxygen enters the blood.
From the lungs. blood goes to the left atrium through pulmonary vein.
From the left atrium, blood goes to the left ventricle.
From the left ventricle, blood is pumped into the aorta so that it can be supplied to different organs.


Short answer.
What will happen if clot is not formed after injury ?

If there are no platelets in the blood, then in case of an injury, bleeding will not stop as blood clot will not be formed. It will result in death due to heavy loss of blood from body.


............ kills the bacteria that enter into the body.

WBC (white bllood cells or Leukocytes) kills the bacteria that enters into the body.


Name the two fluids that circulate in the body

Body fluids are the liquids that flow inside the body and contain a huge amount of water. They are of two types
They are the fluids that are present in the tissues and are also called connective tissue as they connect different tissues and organs. They are of many types like; Blood, Lymph, Cerebrospinal fluid etc.
Blood and lymph are the major fluids and are present in large amounts in the body.


Draw a diagram showing double circulation. 

.

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There are ............ chambers in the heart of the cockroach.

There are 13 chambers in the heart of the cockroach. These are tubular structures which open through the ostium and the peristaltic actions results in the pumping of the fluid. 


Mention any two components of blood.

The main components of blood are:
Red Blood cells-These cells contain haemoglobin and transport oxygen.
White Blood cells- These cells protect the body from infections.
Platelets- They help in blood clotting
Plasma- It transports food, carbon dioxide and nitrogenous wastes in dissolved form.


Why is blood circulation in human heart called double circulation?

In human heart, blood passes through the heart twice during one cardiac cycle. The deoxygenated blood comes to the heart and goes to the lungs for oxygenation. Simultaneously, the oxygenated blood comes to the heart from lungs and goes to different organs. Due to this. blood circulation in human heart is called double circulation. 


Impure blood is brought back to the heart by ............

Impure blood is brought back to the heart by the veins.


What is the function of (a) Platelets (b) Haemoglobin in our body?

a. Platelets- They are cell fragments formed in the bone marrow. They are also called thrombocytes. Platelets carry blood coagulation factors on their surfaces, hence have a major role in initiating and forming blood clots.
b. Haemoglobin- It is a special protein found in the red blood cells that imparts red colour to the blood. It picks up oxygen from lungs to form oxyhaemoglobin and delivers it to the tissues it also carries a small proportion of CO$$_2$$ from the tissues towards the lungs.


What is autogenic transfusion? 

When self blood is used for transfusion, it is called autogenic transfusion. 


Give example for the following.
Open circulatory system is found in _______ where coelomic cavity is filled with blood.

Open circulatory system is found in _______ where coelomic cavity is filled with blood:
Example: Arthropods and Molluscs 


Very Short Answer.
Name the corpuscles that clots the blood.

The corpuscles that clot blood are called platelets or thrombocytes.


Write one function each of the following components of the transport system in human beings.

(a) Blood vessels

(b) Blood platelets

(c) Lymph

(d) Heart

a) Blood vessels - Carry blood for transportation from part of the body to other.

(b) Blood platelets - Helps in blood clotting during injury.

(c) Lymph - Carries digested and absorbed fat for transportation.

(d) Heart - It is a pumping machine which pumps blood to reach all the parts of the body.



_______ ions play a significant role in clotting.

Calcium ions play a significant role in clotting.


Shape of white blood cells.

The shape of white blood cells is amoeboid


What happens if conducting tubes of circulatory system develops a leak?

The blood clots if conducting tubes of a circulatory system develops a leak. The platelets will increase, which will minimize the leakage. Due to this, the inactive thrombin will become the active one in the presence of thromboplasm. Moreover, this active thrombin will convert the inactive fibrinogen into the active fibrin and it results with a clot. The problem is that if the person doesn’t develop with a blood clot, then the medical care is required, otherwise this can lead to death.


Give the difference between open and closed system of circulation.

  Open system of circulation Closed system of circulation
 1It is present in lower organisms, eg., cockroach. It is present in higher organisms, eg., human.
 2In this system blood flows through open spaces thus, blood is in direct contact with tissue fluids.In this system blood flows through closed system of blood vessels thus, blood is in indirect contact with tissue fluids.
 3In this system, blood pressure is low hence, this system is less active than closed system of circulation.

In this system, blood pressure is high hence, this system is more active than open system.


The diagram shows blood vessel P which carries digested food from the small intestine to the liver.
Which row describes the level of glucose in blood vessel P and the level of glycogen in the liver, shortly after a meal containing carbohydrates?
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B is the right answer. Insulin stimulates the liver cells to convert glucose into the storage compound glycogen. This stimulates the liver cells to absorb lot of glucose from the blood so the concentration decreases and returns to normal.


Describe double circulation in human beings. Why is it necessary?

Explanation-

The heart receives deoxygenated blood from different parts of the body, and it pumps this blood to the lungs. The oxygenated blood from the lungs returns to the heart, which is pumped again into different parts of the body by the heart. Thus, the blood passes twice through the heart making one complete round through the body. This is called double circulation.
 
The two circuits involved in double circulation are:
1. Pulmonary circulation: Pulmonary circulation pertains to the lungs. The blood flows from the right ventricle to the lungs. Pulmonary veins collect oxygenated blood from the lungs and carry it back to the heart (left auricle).
 
2. Systemic circulation: Systemic circulation pertains to the major circulation of the body. The aorta receives the blood from the left ventricle and sends it to the various parts of the body. Veins collect the deoxygenated blood from the body parts and pour it back into the right auricle.

Significance of double circulation: The separation of oxygenated and deoxygenated blood allows a more efficient supply of oxygen to the body cells. Blood is circulated to the body tissues through systemic circulation and to the lungs through pulmonary circulation.


Define open and closed type of circulatory systems.

OPEN CIRCULATORY SYSTEM:
  • The blood is pumped by the heart and passes through the large vessels into large cavities or sinuses.
  • The blood comes in direct contact with the tissue cells. 
  • Blood capillaries are absent.
  • The blood is called haemolymph and the tissues through which the blood flows is called haemocoel.
  • This type of circulatory system is found in arthropods and many molluscs.
CLOSED CIRCULATORY SYSTEM:
  • The blood is pumped by the heart and circulated through closed network of blood vessels.
  • The blood does not come in direct contact with the tissue cells.
  • Blood capillaries are present.
  • This type of circulatory system is found in annelids such as Pheretima, and many chordates.



How did you prepare a match-stick stethoscope in your school?

The stethoscope is used to check the pulse, breathing rate and the heartbeat. The pulse can be checked by preparing a stethoscope at home. Take a matchstick and a shirt button. Remove the carbon part of the matchstick. Insert the match stick in the button. Place this button on the wrist. The movements of the wrist due to the pulse can be recorded. This pulse is same as the heart beat. Thus, the heartbeat can be recorded by this method. 


In human beings the blood goes to the heart in one cycle once. Is it true or false?

$$\large\textbf{Solution}$$

$$\textbf{FALSE}$$

$$\bullet$$ $$\textbf{Double circulation}$$ consists of two separate circuits and blood passes through the heart twice.
$$\bullet$$ Two circuits are present- 
1) The pulmonary circuit- Between the heart and lungs
$$\bullet$$ Deoxygenated blood is sent by the right pump to the lungs where it becomes oxygenated and returns back to the heart. 

2) The systemic circuit- Between the heart and the other organs.
$$\bullet$$ With the help of the left pump, the newly oxygenated blood is sent around the body. 

Difference Between Single and Double Circulation | Compare the Difference Between Similar Terms


Lymph plays an important role in protecting immune system of the body. Justify this statement.

The lymph is the fluid which circulates in the lymphatic system. The fluid contains an abundant number of the B-cells, T-cells, macrophages, neutrophils and the other immune cells. These immune cells are involved in providing immunity to the body. These cells are responsible for protecting the body against the diseases. The pathogenic organisms which enter in the lymphatic system are destroyed by these cells. 


What is lymph? Explain its constitution.

Lymph is a colourless fluid that travels through the lymphatic system carrying cells that help fight infection and disease. The plasma, proteins, and white blood cells form the lymph which escapes into the intercellular spaces through the pores present in the wall of capillaries.


What happens if blood platelets are absent in blood?

The blood platelets are required for the process of blood clotting. Whenever there is an injury, to prevent the loss of blood it is necessary to form a clot. The vitamin K, clotting factors, calcium ions and the platelets are necessary agents for the formation of a blood clot. If there are no platelets, there will be no clot formation. This might result in haemorrhage in which there is continuous blood loss. 


Using the data collected by you, from internet and other sources, make a report on coagulation of blood.

Coagulation is the process in which there is formation of a network of cells, proteins and factors to form a clot which prevents the loss of blood from the body. Whenever there is any injury, the blood vessels gets damaged and there is flow of blood outside from the vessels. If the blood keeps on flowing, there will weakness due to loss of blood and cause haemorrhage which may result in death. There are platelets in the blood which gets transformed when there is injury. These platelets invites the clotting factors which are various different proteins which initiate a cascade for the formation of clot. The clot is made up of platelets, clotting factors, neutrophils, macrophages and the fibrin strands. The vitamin K and calcium ions are also essential for the activation of certain proteins involved in this mechanism. 


What will happen if there are no platelets in the blood?

  • Platelets, also known as thrombocytes perform primarily the function of clotting of blood.
  •  If there are no platelets in the blood, a coagulum or a clot will not form and hence, this will result in unstoppable bleeding leading to severe blood loss and ultimately death of the individual.


Short / Long type answer type question.

Why does the lymph contain much less proteins than the plasma?

  • The hydrostatic pressure inside the blood capillaries is greater than that in the tissues, pushing fluid out. The fluid that leaks out into the interstices among the cells is a little of the watery part of the blood plasma, with all the substances it contains except for the larger proteins.
  • Also, a very small fraction of the plasma proteins escape from blood capillaries in the tissues.
  • Hence, lymph contains less proteins than blood plasma. Lymph contains relatively less of the larger proteins compared to plasma suggesting that molecular size is important in lymph filtration.


Which diagram is correct for the circulation of blood through human heart?

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The circulation of blood to and from the heart is as follows:
The blood enters the right atrium (RA) of the heart through the superior and inferior vena cava, passes through the tricuspid valve (between the right atrium and the right ventricle) to reach the right ventricle (RV). The blood from RV is then pumped through the pulmonary artery to the lungs. In the lungs the oxygenation of the blood occurs and then through the pulmonary vein the oxygenated blood enters the left atrium (LA). The blood then enters the left ventricle (LV) (through the bicuspid valve) and is then pumped through the aorta to rest of the body. Thus, the correct diagrammatic representation is seen in option A.

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Write two advantages of hepatic portal system.

Venous blood from the digestive system is taken first to the liver then it is taken back to the heart unlike other systems, where veins carry impure blood directly back to the heart. This system comprises of three vital parts:- Hepatic portal vein, Splenic vein and Superior and inferior mesenteric veins. 
So advantages of Hepatic portal vein are as follows:-
1) The hepatic portal system takes the absorbed nutrients from the digestive tract first to the liver to process them accordingly. After which they are released in normal circulation by the liver.
2) It helps in neutralizing toxic material absorbed by the digestive tract.
3) It helps in waste drainage from the pancreas.
4) It helps in venous drainage from the spleen.


Describe the coronary circulation.

Coronary circulation, part of the systemic circulatory system is the circulation of blood in the blood vessels of the heart muscle (myocardium).
The vessels that deliver oxygen-rich blood to the myocardium are the coronary arteries. Two coronary arteries originate from the left side of the heart at the beginning (root) of the aorta, just after the aorta exits the left ventricle. 
The vessels that remove the deoxygenated blood from the heart muscle and drain them into the right atrium are known as cardiac veins. These include the great cardiac vein, the middle cardiac vein, the small cardiac vein, the smallest cardiac veins, and the anterior cardiac veins.
The heart normally extracts 70 to 75 percent of the available oxygen from the blood in coronary circulation.


Write the differences between blood and lymph.

Answer-

               Blood                          Lymph
 1. Blood is pumped by the heart in the body.
2. Blood carries oxygen in the body.
3. Blood is a red-coloured fluid contain RBC.
4. The flow of blood vessels is fast.
5. The kidneys purify the blood.		1. Lymph moved along by the normal function of the body.
2. Lymph removes waste from the body system.
3. Lymph is a colourless fluid and does not contain RBC.
4. The flow of lymph is slow.
5. Lymph is purified in the lymph node itself.



Given below are groups of terms. In each group the first pair indicates the relationship between the two terms. Rewrite and complete the second pair on a similar basis.
Example : Oxygen : Inspiration : : Carbon dioxide : Expiration
Foetus : Amnion : : Heart : ___________.

The amnion or the amniotic sac is a thin membrane that closely covers the developing embryo until shortly before birth. It is necessary to protect the embryo during pregnancy.
In case of the heart, a double walled conical sac of fibrous tissues that surrounds the heart and the roots of great blood vessels is called the pericardium.
So, the answer is- Foetus : Amnion :: Heart : Pericardium 


Is it possible for the blood to clot under the skin?
Give reason in support of your answer.

It is a wrong notion that clotting is dependent on the exposure of blood to air. In fact,clotting can be caused by the movement of blood over a rough surface as on cholesterol deposit on the inside of a blood vessel.


Red blood cells have no nucleus, then why do we call them cells?

Red Blood Cells are produced in the bone marrow and they have a nucleus when they are initially produced. Later, they lose nucleus in order to accommodate more haemoglobin so that they can transport more amount of oxygen. Therefore they are still considered as cells.


Name the following:
The kind of blood cells which can squeeze out through the walls of one category of blood vessels.

White blood cells can squeeze out through the capillaries.


Name the following:
The blood vessel system which forms two capillary beds.

The blood vessel system which forms two capillary beds is hepatic portal system.


Why is it necessary to know the blood groups before giving transfusion?

Explanation: 
  • The blood group system is also the ABO blood group system.
  • The four major types of blood groups are- A, B, AB and O.
  • Each kind of blood group has its antigen and antibodies.
  • A blood group has A antigen and anti B antibodies and vice-versa for B blood group.
  • O has only anti-A and anti-B antibodies and no antigens.
  • AB has both the antigens but no antibodies.
  • If A receives B blood group, then agglutination occurs that causes RBC death.
  • Therefore, O is the universal donor and AB is the universal recipient.


Given below are certain structures, write the term for the functional activity.
Blood platelets and _________

Blood platelets and blood coagulation.


Why is it necessary to maintain a normal osmotic concentration of the blood?

Explanation:
 In maintenance of normal blood concentration water and salt play vital role. If regulation of water and salt interrupt body either end up losing important salts and water or may accumulate access amount of salts and extra water in our body.


The blood vessel that begins and ends in capillaries is the ______ (hepatic artery, hepatic portal vein, hepatic vein).

The blood vessel that begins and ends in capillaries is the Hepatic portal vein. It connects the liver directly to the other organs of the abdomen. It is the only vein not connected to the heart by any large blood vessel. Instead, it connects other organs of the abdomen by small veins and capillaries. 


Give reason for the following :
The blood groups of both the donor and recipient must be known before transfusing blood.

Sometimes it becomes necessary to inject blood into the body of patients undergoing surgical operation. This is called blood-transfusion. Blood taken from a healthy person(donor) is introduced through one of the patient’s veins. But for doing so, it is necessary that the kind or the type of blood to be transfused should match with the type of blood of the receiving person (recipient).RBC’s of human being have specific glycoproteins on their surface. These proteins are called antigens. The plasma of the blood has its complementary antibodies. Knowing the blood group of the donor and the recipient is required helps matching of the blood antigens so that the blood cells of the donor are not destroyed by the recipients antibodies


Very short answer type.
What is the main function of thrombocytes?

The main function of thrombocytes is to initiate the clotting mechanism. It detects the site of bleeding and initiates blood clot formation.


Name the following:
The mineral element essential for clotting of blood.

Calcium is the mineral element which is essential for the clotting of blood. It is stimulated by the release of thromboplastin from the blood platelets. It is the cofactor of vitamin K which helps in the activation of blood coagulation factors and coagulation of blood.


Very short answer type.
Mention the most significant role of neutrophils.

Neutrophils are the first cells that reach the site of infection whenever required. They can perform phagocytosis by engulfing foreign bodies.


How are blood platelets formed?

Platelets are formed in the bone marrow by segmentation of the cytoplasm (the cell substance other than the nucleus) of cells known as megakaryocytes, the largest cells of the marrow. Within the marrow, the abundant granular cytoplasm of the megakaryocyte divides into many small segments that break off and are released as platelets into the circulating blood. After about 10 days in circulation, platelets are removed and destroyed.
Thus, blood platelets are not cells but are cellular fragments formed by cells called megakaryocytes.


Fill in the blanks with approriate words.
Most carbon dioxide is transported in blood in the form of .......... ions. Hydrogen ions formed when carbon dioxide enters blood become attached to.......... , so that the addition of carbon dioxide causes only a small decrease in blood pH.

Most carbon dioxide is transported in the blood in the form of hydrogen carbonate ions. Due to the formation of hydrogen ions when carbon dioxide enters the blood and attaches to hemoglobin, there is only a small decrease in blood pH.


Very short answer type.
What is serum?

Blood plasma without the clotting factors is a straw colored fluid called serum.


Short / long answer type questions.
A large percentage of carbon dioxide forms carbonic acid within the RBCs whereas very little carbon dioxide forms carbonic acid in the plasma. Why?

  • Only a small percentage (3-5 percent) of carbon dioxide travels dissolved in plasma because of its low solubility. 
  • A major portion (70-75 percent) of C02 is transported as Carbonic acid due to the presence of highly catalyzing enzyme Carbonic acid.


Short / Long type answer type questions.
Why can you palpate the pulse on an artery in each heart beat?

  • Each time the heart contracts, a new pressurized wave of blood is propelled into the arterial side of the circulation.
  • The walls of arteries contain elastic fibers and muscle cells, which enable these blood vessels to expand and contract as waves of blood are propelled through them. 
  • In this way, arterial pulse is created with each heartbeat.


Short / Long type answer type questions.
What are open and closed vascular system? Give two advantages of closed vascular system.

  • Open Circulatory System:
1. Blood flows in open tissue spaces, the sinuses, without proper walls.
2. Blood is in direct contact with the tissue cells.
3. Exchange of materials occurs directly between blood and tissue cells.
4. Blood flow is very slow.
5. Blood has very low pressure.
6. Respiratory pigment, if present, is dissolved in the plasma, no red corpuscles are present.
7. Occurs in arthropods and most molluscs.
  • Closed Circulatory System:
1. Blood flows in closed tubes, the blood vessels, with definite walls.
2. Blood does not come in direct contact with the tissue cells.
3. Exchanged of material between tissue cells and blood occurs via tissue fluid.
4. Blood flow is quite rapid
5. Blood has a high pressure
6. The system is more efficient as the blood flow can be regulated
7. Respiratory pigment is present, and may be dissolved in the plasma but is usually held in red blood corpuscles.
8. Occurs in annelids and vertebrates.
  • Advantages of closed circulatory system over an open circulatory system :
1. Closed system has continuous vessels hence able to generate high pressure
2. Circulates blood over a longer distance
3. Circulates blood at a faster rate
4. Efficient transport of nutrients and waste products
5. Animals are more active


Short / Long type answer type questions.
Give a detailed account of the events of a cardiac cycle and correlate these with an electrocardiogram.

  • The cardiac cycle is the sequence of events in one heartbeat.
It can be divided into three stages:
1. Diastole: The chambers of the heart (atria and ventricles) are relaxed and filling up with blood from the veins. The atrioventricular valves (bicuspid on the left and tricuspid on the right) are open and the semilunar valves (pulmonary and aortic) are closed. This stage lasts for about 0.4 seconds.
2. Atrial systole: the atria contract and top up the ventricles. This takes about 0.1 seconds.
3. Ventricular systole: the ventricles contract and pump blood out of the heart into the arteries. During this stage, the atrioventricular valves are closed and the semilunar valves are open. This takes about 0.3 seconds.
  • A typical human electrocardiogram has five waves – P, Q, R, S, and T.
1. The P-wave indicates atrial depolarization. During this wave, the impulse of contraction is generated by the SA node. The PQ-wave represents atrial contraction.
2. The QR-wave is preceded by ventricular contraction. It represents the spread of the impulse of contraction from the AV node to the wall of the ventricle. It leads to ventricular depolarization.
3. The RS-wave represents a ventricular contraction of about 0.3 sec.
4. The ST-wave represents ventricular relaxation of about 0.4 sec. During this phase, the ventricles relax and return to their normal state.
5. The T-wave represents ventricular relaxation.


Match the definition to the correct term in the given list.
A thin-walled blood vessel that carries blood from capillaries to the heart.
Vein,  cardiac cycle,  cardiac output,  heart rate,  heart beat,  double circulation,  circulatory system,  extracellular fluid,  intercellular fluid,  myogenic heart,  neurogenic heart.

1) Vein - Veins are blood vessels that carry blood towards the heart.
2) Cardiac cycle - It is the performance of the human heart from the beginning of one heartbeat to the beginning of the next one.
3) Heart rate - It is the speed of the heartbeat measured by the number of contractions of the heart per minute.
4) Heartbeat - It may refer to the cardiac cycle of the heart.
5) Double circulation - It is the type of circulation in which blood passes through the heart twice.
6) Circulatory system - The system, which is primarily meant for the circulation of nutritive products in the body is called the circulatory system.
7)  Extracellular fluid - It denotes all the body fluids outside the cell.
8) Intercellular fluid -  it denotes body fluids within the cells.
9) Myogenic heart - It is capable of generating independent cardiac contraction.
10) Neurogenic heart - It is the heart which requires nervous impulse to contract the heart.
So the correct option is Veins. 


Short / Long type answer type questions.
What is the path of blood flow from the heart to the lungs, back to the heart, from the heart to systemic circulation, and back to the heart again?

  • The heart has superior and inferior vena cava. They carry deoxygenated blood from the upper and lower regions of the body respectively and supply the deoxygenated blood to the right atrium of the heart.
  • The right atrium contracts and passes the deoxygenated blood to the right ventricle, through an auriculo-ventricular aperture (tricuspid valve).
  • The right ventricle contracts and passes the deoxygenated blood into the two pulmonary arteries, which pumps it to the lungs where the blood is oxygenated. From the lungs, the pulmonary veins transport the oxygenated blood to the left atrium of the heart.
  • The left atrium contracts and through the auriculo-ventricular aperture (bicuspid valve), the oxygenated blood enters the left ventricle.
  • The blood passes to aorta from the left ventricle. The aorta gives rise to many arteries that distribute the oxygenated blood to all the regions of the body.
  • Since the blood goes twice through the heart, it is known as double circulation.

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Name the arteries that carry deoxygenated blood in humans

The pulmonary artery carries deoxygenated blood. It further divides into two pulmonary arteries one for each lung. 


Match the definition to the correct term in the given list.
A circulatory system in which blood flows through two separate circuits, as pulmonary and systemic.
Vein,  cardiac cycle,  cardiac output,  heart rate,  heart beat,  double circulation,  circulatory system,  extracellular fluid,  intercellular fluid,  myogenic heart,  neurogenic heart.  

1) Vein - Veins are blood vessels that carry blood towards the heart.
2) Cardiac cycle - It is the performance of the human heart from the beginning of one heartbeat to the beginning of the next one.
3) Heart rate - It is the speed of the heartbeat measured by the number of contractions of the heart per minute.
4) Heartbeat - It may refer to the cardiac cycle of the heart.
5) Double circulation - It is the type of circulation in which blood passes through the heart twice.In double circulation, the blood passes twice through the heart during one complete cycle. Double circulation is carried out by two ways, i.e., pulmonary circulation and systematic circulation.
6) Circulatory system - The system, which is primarily meant for the circulation of nutritive products in the body is called the circulatory system.
7)  Extracellular fluid - It denotes all the body fluids outside the cell.
8) Intercellular fluid -  it denotes body fluids within the cells.
9) Myogenic heart - It is capable of generating independent cardiac contraction.
10) Neurogenic heart - It is the heart which requires nervous impulse to contract the heart.
So the correct option is double circulation.


Describe various phases of cardiac cycle in human beings in a stepwise manner.

The cardiac cycle is the process or action carrying within an organism from the beginning of a heart beat to the next one . The cardiac cycle undergoes two phases namely diastole and systole . 
1. In diastole the heart relaxes thus filling in with blood .
2. Followed by the diastole is systole when the heart pumps the blood fillwd in by contraction . 


Match the types of white blood cells listed under column I with the shape of the nucleus given under column II and select the correct option from the codes given below.

  • Neutrophils have a nucleus that consists of two or more lobes joined together by hair-like filaments. 
  • The eosinophil is a specialized cell and generally has a nucleus with two lobes (i.e., bilobed). 
  • Basophils have an S-shaped nucleus. 
  • Monocytes are the largest of all leukocytes. Their nucleus is kidney-shaped. 

So the correct answer is - A-3, B-4, C-2, D-1.



Match column I with column II and select the correct option from the codes given below

A. Heart failure: It may be diagnosed whenever a patient with significant heart disease develops the symptoms of low cardiac output, pulmonary congestion or systemic venous congestion.
B. Cardiac arrest: It is the complete stoppage of the heartbeat i.e., sudden and complete loss of cardiac function.
C. Heart attack: Formation of a clot in a narrowed coronary artery stops the blood supply to the part of the heart muscle beyond the clot.
D. Coronary artery disease( CAD): Atherosclerosis is narrowing of the arteries and arterioles due to deposition of fats, including cholesterol, on their lining.
E. Angina pectoris: Meaning pain in the chest. Deprived of oxygen, the heart muscle experiences constricting pain.
So, the correct answer is 'A-4, B- 5, C-1, D-3, E- 2'.


15.Match the terms given under column 'A' with their functions given under column 'B' and select the answer from the options given below:

A. Lymphatic system: It permeates the entire body. It drains excess tissue fluid from the extracellular spaces back into the blood.
B. Pulmonary vein: Blood takes up oxygen and becomes oxygenated. Four great veins, called pulmonary veins, two from each lung, return the oxygenated blood from the alveolar capillaries to the left auricle.
C. Thrombocytes: They found in vertebrates other than mammals. The spindle cells aid in clotting of blood like the platelets of mammals.
D. Lymphocytes: They secrete antibodies to destroy microbes and their toxins, reject grafts and kill tumour cells.
So, the correct answer is 'A-3, B-1, C- 4,D-2'.



Explain blood circulation in human heart.


Oxygen-poor blood is collected from body parts through superior and inferior vena cava into the right atrium of the heart, which is then pumped to lungs through the pulmonary artery.
Then the oxygen-rich blood from the lungs is transferred to the left atrium through the pulmonary vein, which is then pumped to all other body parts through the aorta.

965148_1026048_ans_49ed845b62534eea9876ccad766c6259.jpg


Why is it necessary to separate oxygenated and deoxygenated blood in mammals and bids? 

Mammals and birds have evolved to sustain a terrestrial life form and homeothermic ability that needs more energy as compared to other life forms. So, it is important to separate the blood coming in from the pulmonary circulation from that going through the systemic circulation. The oxygenated blood is not only rich in oxygen but also moves under high hydrostatic pressure so that it can reach the tissues quickly and metabolism  can be performed at required rate. Also, this type of arrangement is required to maintain the body temperature through the differential contraction of the blood vessels.


Observe the diagram and answer the questions.
Name the group of animals in which we find this kind of mechanism.
1083653_a4a0d131dc5549fab9b5edfe1ce77d0b.jpg

In the given diagram there are two pathways in which blood flows. They are the Pulmonary pathway and Systemic pathway hence it represents a double circulation. The group of animals in which we find this kind of mechanism is mainly in invertebrates ( eg: mammals ) and some invertebrates ( eg: earthworms).


Observe the diagram and answer the questions.
Label the parts 1 to 4.
1083630_1932cc643ebd4873bba50d9a27564ea3.jpg

1- Pulmonary vein: It takes oxygenated blood from lungs to left auricle
2- Systemic artery: It takes oxygenated blood to rest of the body from the left ventricle.
3- Systemic vein: It collects deoxygenated blood from the rest of the body and takes it to the right auricle.
4- Pulmonary artery: It takes deoxygenated blood from the right ventricle to lungs for oxygenation.


What is hypertension? How does it harm us?

Hypertension or High blood pressure is a condition in which there is a persistent rise in blood pressure in the arteries. Symptoms of severe hypertension can include headaches, shortness of breath, nosebleeds, chest pain, visual changes, blood in the urine. When the blood pressure so high that it is in the uncontrolled state it can lead to stroke by damaging and weakening our brain's blood vessels, causing them to narrow, rupture or leak.


Explain double circulation with a schematic diagram?

Double circulation is the most efficient way of circulation. Here, in humans, the four-chambered heart, arteries, veins, and capillaries all have a vital role to play. Blood gets pumped out of the heart. This blood goes to different organs and then blood again comes back to the heart. All this happens in a very systematic way through the different arteries and veins carrying oxygenated and deoxygenated blood.
In double circulation, there are two pathways in which blood flows. They are:
1) Pulmonary pathway   2) Systemic pathway.
The pulmonary circulation or pathway carries the deoxygenated blood from the right side of the heart to the lungs.  Exchange of oxygen and carbon dioxide takes place in the lungs and the blood is now oxygenated (with oxygen). Through the systemic circulation, oxygenated blood travels from the left side of the heart to the other areas of the body. At various organ sites, exchange of gases, nutrients, and waste through lymph occurs. This deoxygenated blood again goes back to the right side of the heart. The pulmonary circuit and the systemic circuit work together. This ensures that deoxygenated blood goes to the lungs through the pulmonary artery while the oxygenated blood from the aorta reaches the different organs and tissues.

986867_1083256_ans_a09e8c45e39d49c19bb8fe4945cac000.png


Discuss nature and role of platelets and lymph.

PLATELETS: Platelets or thrombocyte are the fragments of cytoplasm derived from the megakaryocytes of bone marrow. As they are just fragments they do not have a nucleus or any genetical material. They are formed in bone marrow and enter the blood circulation. The role of platelets is they Secrete vasoconstrictors which constrict blood vessels, causing vascular spasms in broken blood vessels, Form temporary platelet plugs to stop bleeding.,Dissolve blood clots when they are no longer needed.
LYMPH: The colorless fluid which circulates through lymphatic system is called as lymph. Lymph contains a variety of substances, such as proteins, salts, glucose, fats, water, and white blood cells. Unlike your blood, lymph does not normally contain any red blood cells. The role of lymph is it returns proteins and excess interstitial fluid to the bloodstream. It also transports fats from the digestive system to the blood via chylomicrons. 


Ramu got injured while playing Kabaddi. His blood clotted within $$6minuteS$$. Write the procedure involved in it.

Blood clotting or coagulation is the method in which bleeding is controlled when a blood vessel is wounded. Proteins or blood clotting factors are involved in this phase. Normally, a complicated method uses these coagulating factors to cause a fibrin clot that prevents bleeding. Hemostasis is the manner in which the body stops bleeding from wounded blood vessels. Hemostasis involves blood clotting. Hemostasis includes three main procedures: 
1. Blood vessel narrowing (constriction) 
2. Activity of cell-like blood particles helping in blood clotting (platelets) 
3. Activity of blood proteins working with platelets to assist blood clot (clotting factors) like fibrinogen 


Observe the given diagram. Identify and write a brief account of it.
1083624_a289cf5feeea4dff83d4c3b8fe4101eb.png

This diagram shows a double circulation system. 
In our body, the blood flows twice through the heart.
  • During the first phase of circulation, the deoxygenated blood or carbon dioxide-rich blood from the heart is carried to the lungs where it removes carbon dioxide and receives oxygen. The oxygenated blood from the lungs is then carried back to the heart.
  • In the second phase of circulation, the oxygenated blood from the heart is carried to all parts and the deoxygenated blood from the body parts is carried back to the heart. 
Since the blood flows from the heart twice and two separate circulations are involved it is known as a double circulation system.


Find odd one with respect to circulatory system?
1088385_0aa9d85ce530436ab042202ab22c0fd5.jpg

The first organism depicts a human (you). The second figure is that of a mollusk (squid), the third is of an annelid (leech and the last is of another annelid ($${ Nereis }$$).
The circulatory system in humans is the closed type. In squid, as in belongs to the evolved class Cephalopoda, it has a closed circulatory system. $${ Nereis }$$ is an annelid and has a closed circulatory system. But leeches have an open circulatory system despite being annelids.
So the odd one out is Leech (figure 3).


Why is lymph called the 'filtered blood'?

Lymph is formed from the interstitial fluid. The composition of lymph is similar to blood except for the formed elements in it. Thus, the lymph has a composition of blood plasma - the fluid component of blood.
Therefore, lymph is also known as 'filtered blood'.


Platelets releases an enzyme called ______________.

Platelets releases an enzyme called thromboxane. Thromboxane is responsible for the formation of platelet plugs that initiate the cascade of blood clotting reactions.


What do you mean by circulation and circulatory apparatus?

 Circulatory apparatus Circulation
1) The apparatus that allows the circulation of the blood through the organism is called the circulatory apparatus.
2) It consists of the heart, arteries, arterioles, and capillaries.		1) The movement of blood and other substances through the vessels of the body which distribute nutrients and oxygen to and remove waste products from all parts of the body.
2) It consists of pulmonary circulation and systemic circulation.


Why is the lubb and dup sound can be heard?

The lubb and dup sounds of heart are monitored by the stethoscope. The first sound comes due to the closure of the the atrio-ventricular valves. It occurs at the onset of ventricular systole. The second sound of dup is of high pitch. It is caused by the closure of the semilunar valves in the pulmonary artery and the aorta. It occurs at the onset of ventricular diastole.


Write a note on coagulation of blood. 

Blood Coagulation is the process of forming a clot or thrombus in order to prevent excess loss of blood from the body. It is a gel-like mass which is formed by the platelets and fibrin in the blood. A blood clot consists of a plug of platelets enmeshed in a network of water insoluble fibrin molecules. Platelet aggregation and fibrin formation both require the proteolytic enzyme thrombin.
 Clotting also requires:
  • calcium ions (Ca2+)
  • about a dozen other protein clotting factors. Most of these circulate in the blood as inactive precursors. They are activated by proteolytic cleavage becoming, in turn, active proteases for other factors in the system.

Image result for Write a note on coagulation of blood.



Which tissue in our body is responsible for the movement or transportation of substances?

The system that transports nutrients and collects waste materials for disposal in the human body is called the circulatory system. The circulatory system consists of the central organ i.e., the heart, blood vessels and circulating fluid called blood. However, blood never comes in contact with the tissues or the spaces between them, so there exists a parallel system or the lymph system that  collects waste material from the interstitial fluid of the tissues and is also capable of defending the cells from pathogens. 


How many ATP's are produced by consumption of $$1-$$ glucose molecule in RBC?

The red blood cells (RBCs) lack mitochondria. Hence, TCA cycle does not take place in the RBCs. RBCs metabolize glucose mainly via glycolysis followed by lactic acid cycle. The lactate is released from the cells at the end of complete consumption of 1 molecule of glucose. 
Hence, total 2 ATP molecules are produced by consumption of one molecule of glucose in RBC.


Read the statement A,B,C and D. Find out the total number of correct and incorrect statements. 
(A) Normal cardiac output is $$5$$ litre/minute 
(B) Renal vein contain maximum amount of urea 
(C) In mammals each half of pelvic  girdle consist of llium, Ischium and pubis
(D) Sutural joints are found between skull bones
CorrectIncorrect
1.TwoTwo
2.ThreeOne
3.OneThree
4.FourZero

Renal vein carries blood away from the kidney after filteration with minimal amount of Urea.
So, the correct option is 'Three and One'.


Briefly explain the circulatory system.

The circulatory system is the system that supplies tissues with oxygen, blood and other nutrients. It consists of blood, blood vessels, and the heart. It also transports hormones and removes unnecessary waste products.


What disadvantage (if any) would be there. if the human RBCs become biconvex instead of their normal biconcave shape?

The biconcave shape of the RBC facilitates its movement into the smallest of blood vessels, that is , the capillaries which supply O$$_2$$ to the tissue cells. In case, the shape of the RBC is altered to biconvex, its movement through the capillaries will possibly be restricted, leading to less or no supply of oxygen to the tissue cell.



How blood cloating in human being?

The coagulation cascade is a complex chemical process that uses 10 different proteins (called coagulation factors) found in plasma in the blood. Put simply, the clotting process changes blood from a liquid to a solid at the site of injury through given stages :
1. Injury - A small tear in a blood vessel wall causes bleeding.
2. Vessel constriction - To control blood loss the blood vessel narrows, thus limiting blood flow through the vessel.
3. Platelet plug - In response to the injury, cells in the blood called platelets are activated. The platelets stick to one another and to the wound site to form a plug. The protein von Willebrand factor (VWF) helps the platelets stick to each other and to the blood vessel wall.
4. Fibrin clot - Next, clotting factor proteins trigger production of fibrin, a strong, strand-like substance that forms a fibrin clot, a mesh-like net that keeps the plug firm and stable. Over the next several days to weeks, the clot strengthens and then dissolves as the wounded blood vessel wall heals.


List the important functions of lymph.

The lymphatic system has the following functions:

  • Removal of interstitial fluid (lymph) from the tissues.
  • Absorption of chylomicrons and transportation of fats (chyle) from the digestive system.
  • Transportation of leukocytes throughout the body.
  • It constitutes a number of secondary lymphoid organs.


Name the fluid that reaches those parts of the body where blood does not reach. 

The cornea of the eye is the only location in the body that does not have any blood circulation. It is filled with a thick, waxy liquid called the vitreous humour. The oxygen from the air enters into the cornea directly via simple diffusion.


WBCs are called........... of the body.

WBC's are called soldiers of the body. The white blood cells (WBCs) provide immunity to our body. They help in fighting against diseases, infections, allergies, and foreign particles.
Hence, they are called soldiers of the body.


Column II below consists of brief description of organisms in column I. Which of the following  is incorrect match between column I and column II
Column IColumn II
AMillipedeA terrestrial organism with two pairs of jointed appendages attached to each of its many body segments and respires through trachea.
BNerels Numerous setae on leteral appendage called parapodia.
cTaenia sollum Body is covered with cuticle, alimentary canal absent.
dCtenophoresRadially symmetrical, devoid of cnidoblasts, polpy stage present in their life cycle.

Ctenophores are biradially symmetrical, devoid of cnidoblasts and consist of only Medusa stage unlike cnidaria where polyp and Medusa stages are alternative.
So, the correct option is 'Ctenophores - Radially symmetrical, devoid of cnidoblasts, polpy stage present in their life cycle'.


Draw the flow charts of singular circulation and double circulation.


1076980_1214117_ans_9da79ad7b02047e2a1551d5ff7559d07.single%20circulation%2C%20jpg


In mammals and birds why is it necessary to separate oxygenated and deoxygenated blood?

Warm-blooded animals such as birds and mammals maintain constant body temperature by cooling themselves when they are in a hotter environment and by warming their bodies when they are in a cooler environment. Hence, these animals require more oxygen for more cellular respiration so that they can produce more energy to maintain their body temperature.
Thus, it is necessary for them to separate oxygenated and deoxygenated blood, so that their circulatory system is more efficient and can maintain their constant body temperature.


Write the name of instrument used to measure heartbeat.

Heartbeat is the spontaneous and rhythmic contraction and relaxation of the heart to pump out and receive blood to and from the body. Depending upon the nature of control of the heartbeat, the heart has two types, neurogenic myogenic heart.
The number of heartbeat per minute or the number of a cardiac cycle per minute is known as the heart rate which is measured by stethoscope.


Explain how the separation of oxygenated and deoxygenated blood is useful in humans.

Double circulation prevents the mixing of oxygenated and deoxygenated blood with each other. The separation of oxygenated and deoxygenated blood allows a more efficient supply of oxygen to the body cells. It permits blood to circulate and transport nutrients (such as amino acid, electrolytes), oxygen, carbon dioxide, hormones, and blood cells to and from the cells in the body to provide nourishment and help in fighting diseases, stabilizing temperature and ph and maintain homeostasis. 


Explain double circulation in human

The heart receives deoxygenated blood from different parts of the body, and it pumps this blood to the lungs. The oxygenated blood from the lungs returns to the heart, which is pumped again into different parts of the body by the heart. Thus, the blood passes twice through the heart making one complete round through the body. This is called double circulation.

Pulmonary and systemic circulation

The pulmonary circulation pertains to lungs. The blood flows from the right ventricle to the lungs. Pulmonary veins collect oxygenated blood from the lungs and carry it back to the heart (left auricle). 

The systemic circulation pertains to the major circulation of the body. The aorta receives the blood from the left ventricle and sends it to the various parts of the body. Veins collect the deoxygenated blood from the body parts and pour it back into the right auricle.



What is hypertension?

Hypertension is a medical condition when the pressure in the arteries is seen to be raised higher than the normal range .


Distinguish between open and closed circulation.

The difference between open and closed circuit is in open circuit blood is flow through cavities in the body without any vessels whereas in closed circulation there are blood vessels which carry blood from heart to the different body parts


What is Double Circulation?

Solution:

In double circulation, there are two pathways in which blood flows. They are:

  • 1) Pulmonary pathway   2) Systemic pathway.
  • The pulmonary circulation or pathway carries the deoxygenated blood from the right side of the heart to the lungs.  
  • Exchange of oxygen and carbon dioxide takes place in the lungs and the blood is now oxygenated (with oxygen).
  • Through the systemic circulation, oxygenated blood travels from the left side of the heart to the other areas of the body.
  • At various organ sites, exchange of gases, nutrients, and waste through lymph occurs. This deoxygenated blood again goes back to the right side of the heart.
  • The pulmonary circuit and the systemic circuit work together.
  • This ensures that deoxygenated blood goes to the lungs through the pulmonary artery while the oxygenated blood from the aorta reaches the different organs and tissues.



Choose the correct options from the bracket and complete the given paragraph.
(blood, organ transplantation, stem cells, osteocytes, regenerative, pluripotency, adipose connective tissue, liver, embryonic)
_______ are specialised cells that give rise to all other types of cells present in the body of multicellular organisms by the property of ________. These cells are useful in ________ therapy to replaced dead cells in case of conditions like diabetes. The cells are also useful for _________ in case of failure of organs like kidney and liver.

stem cells are specialized cells that give rise to all other types of cells present in the body of multicellular organisms by the property of pluripotency.  These cells are useful in regenerative therapy to replaced dead cells in case of conditions like diabetes. The cells are also useful for organ transplantation in case of failure of organs like kidney and liver.



Briefly describe the transport of $$CO_2$$ in the blood.

CO$$_2$$  can be transported in the blood in the following forms:
  • Dissolved in the blood (solution) directly.
  • In the form of bicarbonate ions, i.e carbon dioxide bound with water to form carbonic acid.
  • Bound with proteins such as haemoglobin to form carbaminohaemoglobin.


There is hypertension due to smoking. Give scientific reason

  1. Smoking causes damage to your blood vessels and the arteries harden, which makes the blood pressure to rise and hence hypertension occurs.
  2. Cigarette smoking or even being exposed to high amounts of second-hand smoke has negative effects on your heart and blood vessels. Not only does nicotine increase your blood pressure but it also boosts your heart rate and causes arteries to narrow and constrict. If the restricted blood flow is long-drawn-out in the arteries, a heart attack or deadly blood clots may result. Cigarette smoking also worsens other health problems related to high blood pressure such as pulmonary problems. Even light smoking can increase the risk of hypertension. There is good evidence that 1 to 4 cigarettes per day raises the risk of coronary heart disease.


Describe double circulation in human beings schematically. Why is it necessary?

Double circulation of blood helps keep oxygenated (blood rich in oxygen) separate from deoxygenated (blood rich in carbon dioxide). This results in more efficient circulation of blood because a greater amount of oxygen-rich blood can be delivered to the tissues and it also maintain constant body temperature.
1178657_1290075_ans_89c31961ae60477ca6922f85bc0e40e2.jpg


Which one function of the following component of transport system in human beings.
Lymph.

Lymph carries digested and absorbed fat from intestine and drains excess fluid from extra cellular space back into the blood.


Complete the paragraph given below by filling in the blanks.

Blood flows twice in the heart. In pulmonary circulation, the deoxygenated blood is carried to the ________ from the __________ of the heart, through the ________. The oxygenated blood from the lungs is carried back to the ________ of the heart through the __________. This oxygenated blood from the heart is carried to all systems of the body and the deoxygenated blood from the systems below and above the heart is supplied to the ________ of the heart through the _________.

Blood flows twice in the heart. In pulmonary circulation, the deoxygenated blood is carried to the lungs from the right ventricle of the heart, through the pulmonary artery. The oxygenated blood from the lungs is carried back to the left atrium of the heart through the pulmonary vein. This oxygenated blood from the heart is carried to all systems of the body and the deoxygenated blood from the systems below and above the heart is supplied to the right atrium of the heart through the vena cava.
Since the blood flows in the heart twice, therefore this circulation is known as double circulation.


Why is human heart called double pump ?

The human heart is a single organ, but it acts as a double pump. The first pump carries oxygen-poor blood to the lungs, where it unloads Carbon dioxide and picks up Oxygen. It then delivers Oxygen-rich blood back to the heart. The second pump delivers Oxygen-rich blood to every part of the body.


Give reasons.
How can we feel the beating of the heart?

We feel the beating of heart by pulse. 
Place your index and middle finger of your hand on the inner wrist of the other arm, just below the base of the thumb.

You should feel a tapping or pulsing against your fingers.

Count the number of taps you feel in 10 seconds.

Multiply that number by 6 to find out your heart-rate for one minute:

Pulse in 10 seconds x 6 = \__ beats per minute (your heart-rate)

When feeling your pulse, you can also tell if your heart rhythm is regular or not.


How many types of circulatory systems are found in animals?

There are two types of circulatory systems, found in animals. They are:
Open type circulation: 
1. In this blood spreads out through large open spaces called sinuses, within the tissues of the body. 
2. Body tissues are in direct contact with blood. 
3. The volume of blood flouring in tissues cannot be regulated. 
4. There is no heart.
For example Insects like a grasshopper, cockroach, etc. 

Closed type Circulation: 
1. The circulatory blood remains confined within the blood vessels at all times. It does not spread in open spaces. 
2. Body tissues are not in direct contact with blood. 
3. The volume of blood flowing through tissue or organ can be controlled by contraction and relaxation of muscles of arteries. 
4. The heart is present, which works like a pumping station. 
For example Earthworm. Man (Human beings).


Explain the importance of inheritance of blood group.

Inheritance of blood groups has many uses like in settling disputes related to parentage of a child, in blood transfusion, in treating haemophilia patient, etc. 
The given diagrams illustrate an example of how parentage of a child can be confirmed. Let us assume that a child's blood group is B. In case of first couple, husband's blood group is O and wife's blood group is AB. In case of second couple, husband's blood group is A and wife's blood group is B. The diagram shows possible blood groups in child from each couple. It clearly shows that a child with blood group B is possible only in case of the first couple. 
1853079_1835758_ans_ffaa452f931245e18a33442c1c95073b.png


Briefly explain Rh incompatibility in blood transfusion. 

Rh factor matching is also important for blood transfusion. If Rh positive blood is transfused to an Rh negative person then recipients body produces IgG antibodies. These antibodies destroy RBCs by agglutination. This results in increased levels of bilirubin in blood which adversely affects the liver and spleen. As a result, the person dies due to renal failure. 


Write the precautions which need to be taken during blood transfusion. 

Following precautions need to be taken during blood transfusion: 
• Blood groups of donor and recipient must be matched. 
• Rh factor matching should be done. 
• Donor's blood should be checked for presence of any infection. 
• Donated blood should be collected in a sterilized container. 


Explain the process of blood transfusion.

Process of Blood Transfusion: 
Blood Collection: 
• Thorough health checkup of the donor. 
• Blood is collected in sterilized anticoagulant containing pouch with the help of a cannula. 
• Collected blood is stored at low temperature. 
• Blood is checked for any infection like hepatitis, HIV, etc. and is also checked for ABO grouping and Rh factor. 

Blood Transfusion: 
• Donor's blood is matched with recipient's blood for ABO grouping and Rh factor. 
• Stored blood is taken out of refrigerator about 30 minutes before actual transfusion. 
• Blood is transfused intravenously and the process takes about 4 hours. 
• The recipient is continuously monitored for any untoward reaction. 


Define heart-beat. 

One complete contraction and relaxation of the heart is called a heartbeat. 


Very Short Answer.
What is the function of blood platelets ?

The main function of blood platelets is to help in clotting of blood. It helps stop the flow of blood  during an injury.


Given below are the abnormal conditions related to blood circulation. Name the disorders. 
(a) Acute chest pain due to failure of $$O_2$$ supply to heart muscles
(b) Increased systolic pressure

$$\textbf{Explanation:}$$

$$\text{a)}$$ Acute chest pain due to failure of $${O_2}$$ supply to heart muscles: Angina

$$\bullet$$ It is also called 'angina pectoris. The term angina pectoris means chest pain.

$$\bullet$$ A symptom of acute chest pain appears when not enough oxygen reaches the heart muscles. 

$$\bullet$$ It can occur in both men and women of any age but it is more common among middle-aged and elderly people.

$$\text{b)}$$ Increased systolic pressure- Hypertension

$$\bullet$$ Hypertension is a term for blood pressure that is higher than normal.

$$\bullet$$ A blood pressure of 120/80 is considered normal. In this measurement, 120 mm Hg (millimeters or mercury) is the systolic, or pumping pressure and 80 mm of Hg is the diastolic, or resting, pressure.

$$\bullet$$ If repeated checks of blood pressure of an individual is 140/90 or higher, it shows hypertension which leads to heart diseases and also affects vital organs like brain and kidney.


Write the features that distinguish between the two
Open and closed circulatory system

Open circulatory systemClosed circulatory system
i)Blood Is directly showered on target organs.i)Blood is supplied to organs through a closed network of vessels.
ii)Respiratory pigment is absent in most of the cases.ii)Respiratory pigment Is present In all cases.
iii)Present in arthropods and molluscs.iii)Present in annelids, and all vertebrates. 


Given below is the diagrammatic representation of a standard ECG. Label its different peaks. 
1848070_53866843f9734a3380ccb206c49e3aa9.png


2037534_1848070_ans_872f27168db04a5193939010a397042a.png


Short Answer.
Differentiate between:
(a) Open circulatory system and closed circulatory system
(b) Oviparous and viviparous characteristic
(c) Direct development and indirect development

$$\textbf{Open circulatory system}$$$$\textbf{Closed circulatory system}$$
In the open circulatory system blood is pumped by heart into a cavity called haemocoel and all the organs and tissues come in direct contact with the blood i.e. the organs and tissues get bathed in the pool of blood.
Blood vessels are absent. 		In a closed circulatory system, blood flows through a network of vessels.Organs and tissues never come in direct contact with the blood.
Blood vessels like arteries, veins and capillaries are found.

Example: Arthropods and molluscs.Example: Annelids and vertebrates.
$$\textbf{Oviparous characterisic}$$$$\textbf{Viviparous characteristic}$$ 
Oviparous animals lay eggs and
young ones hatch from the eggs. 		Viviparous animals give birth to young ones. 
Example: amphibians, reptiles and birds.Example: mammals.
$$\textbf{Direct development}$$$$\textbf{Indirect development}$$
In direct development, the embryo develops into a mature individual without involving a larval stage. Metamorphosis is absent.
In indirect development embryo first develops into a larva, and larva undergoes metamorphosis to change into a adult.
Example: Fishes, reptiles, birds, mammals.Example: Echinoderms, arthropods and amphibians


What is double circulation? What is the benefit of double circulation? 

 In humans, blood passes through the heart twice during a cardiac cycle. Once, the deoxygenated blood passes through the heart and then the oxygenated blood passes through the heart. This is called double circulation. In this case, deoxygenated blood is completely separated from oxygenated blood. Hence, this is a highly efficient method of blood circulation. Animals which show double circulation are more active, more energetic and are warm blooded animals. Double circulation is present in mammals and birds. 


What physiological circumstances lead to erythroblastosis foetalis? 

$$\textbf{Explanation:}$$

$$\bullet$$ Another group of antigens other than A and B are found on the red blood cells of most people and is called Rh factor (Rh stands for Rhesus monkey).

$$\bullet$$ People who have these antigens are called Rh +ve, whereas those who do not are called Rh-ve.

$$\bullet$$ An Rh -ve person, if exposed to Rh +ve blood, will form specific antibodies against the Rh antigen.

$$\bullet$$ A special case of Rh incompatibility (mismatching) has been observed between the Rh -ve blood of a pregnant mother with Rh +ve blood of the fetus.

$$\bullet$$ The Rh -ve mother is not usually exposed to the Rh antigen of the fetus during the first pregnancy as the fetal blood and maternal blood are normally kept well separated by the placental barrier.

$$\bullet$$ However, at the time of the birth of the first child, there is a possibility of exposure of the maternal blood to small amounts of the Rh +ve blood from the fetus. In such cases, the mother starts preparing antibodies against Rh antigen in her blood.

$$\bullet$$ These antibodies could cross the placental barrier in subsequent pregnancies and cause hemolysis of the Rh +ve red blood cells of the fetus.

$$\bullet$$ This could be fatal to the fetus or could cause severe anemia and jaundice to the baby ( HDN- hemolytic disease of the newborn). This condition is called erythroblastosis foetalis.

Rh factor may be responsible for which of the following disease?


(a) Draw a sectional view of human heart and label on it aorta. pulmonary vein, vena cava, left ventricle.
(b) Why is double circulation of blood necessary in human being?

(a) Labelled diagram of heart.
(b) The blood passes through the heart twice. Right side of the heart receives deoxygenated blood which is circulated to lungs for Oxygenation. At the same time the left side of the heart receives oxygenated blood which is circulated to the body. This is called double circulation. 
1764507_1836938_ans_938da070cbe742168132d3246d661e0c.png


Short Answer.
Differentiate between :
(a) Open and closed circulatory system
(b) Oviparity and viviparity
(c) Direct and indirect development
(d) Acoelomate and pseudocoelomate
(e) Notochord and nerve cord
(f) Polyp and medusa

$$\textbf{Open circulatory system}$$$$\textbf{Closed circulatory system}$$
In the open circulatory system blood
is pumped by heart into a cavity called
haemocoel and all the organs and tissues come in direct contact with the blood i.e. the organs and tissues get bathed in the pool of blood.
Blood vessels are absent. 
In a closed circulatory system, blood flows through a network of vessels.Organs and tissues never come in direct contact with the blood.


Blood vessels like arteries, veins and capillaries are found.
Example: Arthropods and molluscs.Example: Annelids and vertebrates.
$$\textbf{Oviparous characterisic}$$$$\textbf{Viviparous characteristic}$$  
Oviparous animals lay eggs and young ones hatch from the eggs. Viviparous animals give birth to young ones. 
Example: Amphibians, reptiles and birds.Example: Mammals.
$$\textbf{Direct development}$$$$\textbf{Indirect development}$$
In direct development, the embryo develops into a mature individual without involving a larval stage.
Metamorphosis is absent.		In indirect development embryo first develops into a larva, and larva undergoes metamorphosis to change into a adult.
Example: Fishes, reptiles, birds, mammals.Example: Echinoderms, arthropods and amphibians
 $$\textbf{Acoelomates}$$ $$\textbf{Psedocoelomates}$$
Organisms which does not have a body cavity or true coelom are called acoelomates.Pseudocoelomates are those, which have a body cavity which is not lined completely with mesoderm.
Instead, the mesoderm is present as scattered pouches in between the ectoderm and endoderm.
Example: Platyhelminthes ($$Fasciola$$).Example: Aschelminthes ($$Ascaris$$).
$$\textbf{Notochord}$$ $$\textbf{Nerve cord}$$
Notochord is an ensheathed flexible rod of turgid cells present in chordates. It is  ventral to nerve cord in chordates.Nerve cord is a collection of nerve fibres that runs throughout the length of an animal. It is found in both non chordates and chordates.
Notochord is mesodermalNervecord is ectodermal
$$\textbf{Polyp}$$
 $$\textbf{Medusa}$$
Polyp is a body form present in phylum cnidaria.
They are diploid, cylindrical and sessile 
Medusa is also a body form present in phylum Cnidaria.
These are free-swimming, diploid, umbrella-like.
 They reproduce asexually.
Example : Hydra		They reproduce sexually.
Example : Aurelia





What is circulatory system? Write the names of circulatory fluids and materials which they transport.

The circulatory system includes the lymphatic system, which circulates lymph, Blood is a fluid which consists of plasma, red blood cells, white blood cells, and platelets that is circulated by the heart through the arteries and veins carrying oxygen and nutrients to and waste materials away from all body tissues.


Write short note on -Coronary Artery Disease

Answer:

∙∙
  •  Coronary artery disease is often referred to as atherosclerosis.
  •  It refers to the deposition of fatty substances especially cholesterol and triglycerides in the tunica interna and smooth muscles of medium-sized and large arteries. 
  •  Such depositions are called atherosclerotic or atheromatous plaque which deforms the arterial wall.
  •  Gradually these plaques grow. As a result, the lumen of the artery decreases, and the flow of the blood is reduced. In extreme cases, these plaques may block the artery completely.
  •  If such plaques are formed in the coronary arteries the latter reduces the blood supply to the heart or may stop the blood supply due to complete blockage of the coronary arteries.
  •  This may result in a heart attack or stroke.

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Write a difference between open and closed circulatory system. 

Difference between open and closed circulatory system
1. Open Circulatory system: 
In open circulatory system the hemolymph circulates between cells and tissues, openly i.e. does not flow in closed blood vessels. 
Example: Molluscs and Arthropods. 
2. Closed Circulatory system: 
In a closed circulatory system, the fluid flows within closed vessels and does not come in direct contact with the cells or tissues.
Example: Human and Rabbit etc. 


Write short note on : Hypertension 

Hypertension is elevated blood pressure. Normal blood pressure in an adult is 120/80 mm Hg. The pressure on the higher side is called systolic blood pressure. while that on the lower side is called diastolic blood pressure. If blood pressure consistently shows 140/90 mm fig or more in successive readings, then the person can be diagnosed to be suffering from hypertension. Hypertension can have serious long term repercussions because it can give rise to coronary artery disease, damage to kidneys, liver, retina and brain. 


Amoeboid cells in humans.

White blood cells are amoeboid cells in humans that can squeeze out through the capillary walls.


Why do red blood cells have no nucleus?

Red blood cells have adapted this characteristic (no nucleus) for several reasons are as follows:
1. It simply allows the red blood cell to have more hemoglobin. The more hemoglobin the more oxygen molecules can bound. Therefore, it allows RBC to transfer more oxygen.
2. Lack of nucleus in RBC also allows the cell to have a unique biconcave shape that helps in diffusion.


What are the main function of connective tissue?

Main function of connective tissues are: (i)Helps in binding of tissues ,(ii)Supports various organs of the body.


What is meant by double circulation? What is its significance?

  • Double circulation is a process during which blood passes twice through the heart during one complete cycle. This type of circulation is found in amphibians, reptiles, birds, and mammals. However, it is more prominent in birds and mammals as in them the heart is completely divided into four chambers – the right atrium, the right ventricle, the left atrium, and the left ventricle.
The movement of blood in an organism is divided into two parts:
(i) Systemic circulation
(ii) Pulmonary circulation
  • Systemic circulation involves the movement of oxygenated blood from the left ventricle of the heart to the aorta. It is then carried by blood through a network of arteries, arterioles, and capillaries to the tissues. From the tissues, the deoxygenated blood is collected by the venules, veins, and vena cava, and is emptied into the left auricle.
  • Pulmonary circulation involves the movement of deoxygenated blood from the right ventricle to the pulmonary artery, which then carries blood to the lungs for oxygenation. From the lungs, the oxygenated blood is carried by the pulmonary veins into the left atrium.
Hence, in double circulation, blood has to pass alternately through the lungs and the tissues.
  • Significance of double circulation:
The separation of oxygenated and deoxygenated blood allows a more efficient supply of oxygen to the body cells. Blood is circulated to the body tissues through systemic circulation and to the lungs through the pulmonary circulation.


Draw a standard ECG and explain the different segments in it.

Answer-

Electrocardiogram is a graphical representation of the cardiac cycle produced by an electrograph. The diagrammatic representation of a standard ECG is shown below.

                                     standard ECG

A typical human electrocardiogram has five waves – P, Q, R, S, and T. The P, R, and T-waves are above the base line and are known as positive waves. The Q and S-waves are below the base line and are known as negative waves. The P-wave is of atrial origin, while the Q, R, S, and T-waves are of ventricular origin. 

(a) The P-wave indicates atrial depolarisation. During this wave, the impulse of contraction is generated by the SA node. The PQ-wave represents atrial contraction.

(b) The QR-wave is preceded by ventricular contraction. It represents the spread of the impulse of contraction from the AV node to the wall of the ventricle. It leads to ventricular depolarisation.

(c) The RS-wave represents ventricular contraction of about 0.3 sec.

(d) The ST-wave represents ventricular relaxation of about 0.4 sec. During this phase, the ventricles relax and return to their normal state.

(e) The T-wave represents ventricular relaxation.



ECG depicts the depolarisation and repolarisation processes during the cardiac cycle. In the ECG of a normal healthy individual one of the waves are not represented. Which wave is that? Explain.

The wave of atrial repolarization is invisible due to low amplitude. Atrial repolarisation coincides with ventricular depolarization, so it is merged with the QRS complex and thus, is not recorded as a separate wave. So, the wave of atrial repolarization is not represented.


(a) Explain the process of nutrition in amoeba with the help of a diagram.
(b) With the help of a flow chart explain the process of circulation of blood between human heart and body?

The mode of nutrition in amoeba is holozoic. 
Mechanism of Nutrition
Ingestion : The food is ingested at the point where it comes in touch with the cell surface with the help of pseudopodia. Pseudopodia engulf the food into the cytoplasm. 
Invagination: Pseudopodia secretes a sticky and toxic fluid which adheres and kills the prey. It is then taken in by invagination.
Pinocytosis: Also called cell drinking. There are pinocytosis channels at certain points through which the cell ingests the food digestion in amoeba takes place. The food taken in remains in a food vacuole or gastric vacuole formed by the cell membrane and small part of the cytoplasm. The vacuoles are transported deeper into the cells by cytoplasmic movements. Here they fuse with lysosomes that contain enzymes. Two enzymes amylase and proteinase have been reported. Thus, amoeba can digest sugars, cellulose and proteins. Fats, however, remain undigested.
The contents of the vacuole become lighter and the outline of the vacuole becomes indefinite indicating that the digestion is complete.

(b)   Circulation of blood between heart and body

                             Right atrium
                                      I            Right atrioventricular valve
                                      I
                                     V
                             Right ventricle
                                      I                 Right semilunar valve
                                      I                  Pulmonary artery
                                     V
                                 Lungs
                                     I                   Pulmonary vein
                                     I
                                    V
                              Left atrium
                                      I                 Left atrioventricular valve
                                      I
                                     V
                               Left ventricle
                                      I                  Left semilinar valve
                                      I                   Aorta
                                     V
                                    Body
                                      I               Vena cava 
                                      I
                                     V
                               Right atrium

The human circulatory system is really a two-part system whose purpose is to bring oxygen-bearing blood to all the tissues of the body. When the heart contracts it pushes the blood out into two major loops or cycles. In the systemic loop, the blood circulates into the body’s systems, bringing oxygen to all its organs, structures and tissues and collecting carbon dioxide waste. In the pulmonary loop, the blood circulates to and from the lungs, to release the carbon dioxide and pick up new oxygen. The systemic cycle is controlled by the left side of the heart, the pulmonary cycle by the right side of the heart. 

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Write the differences between :
Open and closed systems of circulation

 Open system of circulation  Close system of circulation
(1) Blood does not remain confined in the blood.
(2) Blood flows at low pressure.
(3) Blood flows at low pressure.
(4) Exchange of materials is direct between blood and body cells.
(5) It is less efficient.
(6) Found in leech, prawns, crabs, lobsters, insects, pila, etc		(1) Blood remains confined in the blood.
(2) Blood flows at high pressure. 
(3) Blood flows at high pressure.   
(4) Exchange of materials occurs through the tissue fluid.
(5) It is more efficient.
(6) Found in Nerels, earthworm, squid and all vertebrates.


Very short answer type.
What is the name of the straw coloured fluid left after clotting of blood?

After clotting of blood, all the clotting factors when removed from it leaves behind a straw colored fluid which is called serum.


Expand PDGF. What is its significance?

PDGF stands for Platelet Derived Growth Factor.
It is one of the many growth factors present in the body which regulates cell growth and division.
It is the chemical released by the breaking of platelets.Though PDGF is synthesized, stored and released by platelets upon activation, it is also produced by other cells including smooth muscle cells, activated macrophages, and endothelial cells.
PDGF plays a significant role in blood vessel formation, the growth of blood vessels from already-existing blood vessel tissue, mitogenesis, i.e. proliferation, of mesenchymal cells as well as chemotaxis, the directed migration, of mesenchymal cells.



Describe in brief the process of blood-clotting.

Coagulation, also known as clotting, is the process by which blood changes from a liquid to a gel, forming a blood clot. It potentially results in hemostasis. The mechanism of coagulation involves activation, adhesion, and aggregation of platelets along with deposition and maturation of fibrin. Fibrin is formed by the conversion of inactive fibrinogens in the plasma by the enzyme thrombin. Thrombin formed from another inactive substance called prothrombin. An enzyme thrombokinase is required in the above reaction. This is a series of linked enzymatic reactions called the cascade process.


Short / Long type answer type questions.
Which would cause a greater increase in resistance to flow-a doubling of blood viscosity or a halving of tube radius?

Halving 0f the tube radius will have a greater resistance to blood flow. Resistance is directly proportional to blood viscosity but inversely proportional to the fourth power of tube radius. 



Differentiate between.
Venous heart and pulmonary heart

Venous heart is 2-chambered (one auricle and one ventricle), and with a single circuit of blood circulation. Whereas in pulmonary heart there is double circulation.


Fill in the blanks with approriate words.
An accumulation of unusually large quantities of interstitial fluids is called..........

An accumulation of unusually large quantities of interstitial fluids is called "edema".


Short / Long type answer type questions.
Normally, each side of the heart pumps the same volume of blood per minute. What would happen if one side were weakened by disease?

If one side of the heart were weakened by disease then blood flow to the heart muscle becomes slow or may stop.


Short / Long type answer type questions.
What is double circulation? Describe it with reference to human heart.

  • A circulatory system in which blood travels twice through the heart in one complete cycle of the body is called Double circulation. 
  • In the human circulatory system, the pathway of blood from the heart to the rest of the body and back to the heart is called systemic circulation; and the pathway of blood from the heart to the lungs and back to the heart is called pulmonary circulation. These two types of circulation taken together makes Double circulation.


What is a circulatory system?

The circulatory system is made up of a circulatory fluid connective tissue called blood, a pumping organ called the heart, and the blood vessels called arteries, veins and capillaries. Blood is made up of plasma and formed elements of cells. It transports oxygen, nutrients, drugs, hormones to the tissues and carries away the waste of carbon dioxide, urea, uric acid etc. The heart is responsible for differentiating the oxygenated and the de-oxygenated blood and pumps it to the whole body. The blood vessels are distributed throughout the body. In the arteries, blood moves away from the blood t the tissues. It is generally oxygenated blood. In the veins, the blood moves towards the heart from the tissues. It is generally deoxygenated.


Explain the process of double circulation with the help of a flow chart.

Explanation-

  • Double circulation is a type of circulatory system, where the heart pumps the blood twice to perform its function.
  • The first pumping sends the blood to be circulated through the lungs, and the second pumping circulates the blood throughout the body. 
  • The right side of the heart accepts blood that has been circulated throughout the body and pumps it at relatively low pressure to the lungs.
  • In the lungs, the blood is replenished with oxygen. 
  • Once the blood has been completely circulated through the lungs, it returns to the heart.
  • Arriving at the much larger left side of the heart, the blood is then pumped out to the entire body. 

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Class 11 Medical Biology Extra Questions