Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Bio Zoology Guide Pdf Chapter 7 Body Fluids and Circulation Text Book Back Questions and Answers, Notes.

   

Tamilnadu Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

11th Bio Zoology Guide Body Fluids and Circulation Text Book Back Questions and Answers

Part I

I. Choose The Best Options

Question 1.
What is the function of lymph?
a. Transport of O2 into brain
b. Transport of CO2 into lungs
c. Bring interstitial fluid in blood
d. Bring RBC and WBC in lymph node
Answer:
c. Bring interstitial fluid in blood

Question 2.
Which one of the following plasma proteins is involved in the coagulation of blood?
a. Globulin
b. Fibrinogen
c. Albumin
d. Serum amylase
Answer:
b. Fibrinogen

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 3.
Which of the following WBCs are found in more numbers?
a. Eosinophil
b. Neutrophil
c. Basophil
d. Monocyte
Answer:
b. Neutrophil

Question 4.
Which of the following is not involved in blood clotting?
a. Fibrin
b. Calcium
c. Platelets
d. Bilirubin
Answer:
d. Bilirubin

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 5.
Lymph is colourless because
a. WBC are absent
b. WBC are present
c. Haemoglobin is absent
d. RBC are absent
Answer:
d. RBC are absent

Question 6.
Blood group is due to the presence or absence of surface
a. Antigens on the surface of WBC
b. Antibodies on the surface of RBC
c. Antigens on the surface of RBC
d. Antibodies on the surface of WBC
Answer:
c. Antigens on the surface of RBC

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 7.
A person having both antigen A and antigen B on the surface of RBCs belongs to blood group
a. A
b. B
c. AB
d. O
Answer:
c. AB

Question 8.
Erythroblastosis foetalis is due to the destruction of
a. Foetal RBCs
b. Foetus suffers from atherosclerosis
c. Foetal WBCs
d. Foetus suffers from mianmata
Answer:
a. Foetal RBCs

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 9.
Dub sound of heart is caused by
a. Closure of atrio-ventricular valves
b. Opening of semi-lunar valves
c. Closure of semi-lunar values
d. Opening of atrio-ventricular valves.
Answer:

Question 10.
Why is the velocity of blood flow the lowest in the capillaries?
a. The systemic capillaries are supplied by the left ventricle, which has a lower cardiac output than the right ventricle.
b. Capillaries are far from the heart, and blood flow slows as distance from the heart increases.
c. The total surface area of the capillaries is larger than the total surface area of the arterioles.
d. The capillary walls are not thin enough to allow oxygen to exchange with the cells.
e. The diastolic blood pressure is too low to deliver blood to the capillaries at a high flow rate.
Answer:
c. The total surface area of the capillaries is larger than the total surface area of the arterioles.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 11.
An unconscious patient is rushed into the emergency room and needs a fast blood transfusion. Because there is no time to check her medical history or determine her blood type, which type of blood should you as her doctor, give her?
a. A
b. AB
c.  Q+ve
d. O ve
Answer:
d. O ve

Question 12.
Which of these functions could or could not be carried out by a red blood cell?
a. Protein synthesis
b. Cell division
c. Lipid synthesis
d. Active transport
a. Protein synthesis – Red blood cells have no DNA.
b. Cell division – Red blood cells have no nucleus. So do not undergo any mitosis and mesiosis.
c. Lipid synthesis – Red blood contains none of the cellular orgakelles.
d. Active transport – Yes, RBC transport O2 and CO2 with in the cell.
Answer:
d. Active transport – Yes, RBC transport O2 and CO2 with in the cell.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 13.
At the venous end of the capillary bed, the osmotic pressure is
a. Greater than the hydrostatic pressure
b. Result in net outflow of fluids
c. Results in net absorption of fluids
d. No change occurs.
Answer:
a. Greater than the hydrostatic pressure

Question 14.
A patient’s chart reveals that he has a cardiac output of 75G0mL per minute and a stroke volume of 50 mL. What is his pulse rate (in beats/min)
a. 50
b. 100
c. 150
d.400
Answer:
c. 150

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 15.
At any given time there is more blood in the venous system than that of the arterial system. Which of the following features of the veins allows this?
a. relative lack of smooth muscles
b. presence of valves
c. proximity of the veins to lymphatic’s
d. thin endothelial lining
Answer:
b. presence of valves

Question 16.
Distinguish between arteries and veins.
Answer:

Arteries Veins
1. They carry blood away from the heart They carry blood from the parts of the body towards the heart.
2. They lie deep inside the body. They lie on the surface beneath the skin.
3. The walls are thick and non-collapsible They have thinner walls.
4. There are no valves. They have valves.
5. Except for the pulmonary artery all the arteries carry oxygenated blood. Except for the pulmonary vein, all the veins carry deoxygenated blood.
6. Blood pressure is high in the arteries Blood pressure is low in the veins.
7. A small sphincter lies at the junction between the arterioles and capillaries to regulate the blood supply. There is no sphincter muscles

Question 17.
Distinguish between open and closed circulation
Answer:

Open circulation Closed circulation
1. The blood pumps from the heart pass into the coelom through blood vessels. The body cavity is known as haemocoel. The blood pumps from the heart push into the blood vessels.
2. (Eg.) Arthropoda Mollusca (Eg.) Annelida vertebrates

Question 18.
Distinguish between the mitral valve and semilunar valve.
Answer:

Mitral valve Semilunar valve
1. It guards the opening between the left atrium and left ventricle It guards the opening of the pulmonary artery and aorta.
2. It allows the blood to flow from auricle to ventricle It allows the blood to flow from the ventricle to the pulmonary artery and aorta.
3. It prevents the backflow of blood It prevents the backflow of blood.
4. The mitral valve closes during contraction of heart and produces a sound lub. The dub sound is produced due to the closure of lunar valves on dialation of heart
5. The chordae tendinae is not connected to this valve. The chordae tendinae is connected to this valve.

Question 19.
The right ventricular wall is thinner than the left ventricular wall. Why?
Answer:
The right ventricle pumps deoxygenated blood, to the lungs through pulmonary artery. The left ventricle pumps the oxygenated blood to all parts of the body through the aorta. Hence, left ventricle has to exert more pressure. Hence right ventricular wall is thinner but the left ventricular walls is thicker.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 20.
What might be the effect on a person whose diet has less iron content?
Answer:

  • The number of red blood cells decreases.
  • Due to the depletion of haemoglobin he finds it difficult to breath.
  • Due to the deficiency of iron anaemia may develop.
  • Due to the deficiency of iron, the oxygen-carrying capacity of haemoglobin reduces.

Question 21.
Describe the mechanism by which the human heartbeat is initiated and controlled.
Answer:

  • The human heart is myogenic in nature.
  • The heartbeat is originated from a pacemaker. The total rate of heartbeat is decided by this node.
  • This pacemaker is situated in the right sinuatrial node.
  • On the left side of the right atrium is a node called auricula ventricular node.
  • Two special cardiac muscle fibres originate from the auriculo ventricular node and are called the bundle of His which runs down into the interventricular septum and the fibres spread into the ventricle called Purkinje fibres.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation 1

Origin of heartbeat:

  • Pacemaker cells produce excitation through depolarisation of their cell membrane. The j excitation is spread in to the auricle. Then this is passed on to bundle of His through auriculo ventricular node.
  • The purkinje fibres cause ventricular contraction.

Regulation:

  • The pacemaker cells produce excitation through depolarisation of their cell membrane. Each polarisation is slow taken place by sodium influx and reduction in potassium efflux.
  • Minimal potential is required to activate voltage gated calcium (Ca+) channels that causes rapid depolarisation which results in action potential.
  • The pacemaker cells repolarise slowly via K+ efflux.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 22.
What is lymph? Write its function.
Answer:
About 90% of fluid that leaks from capillaries eventually seeps back into the capillaries and the remaining 10% is collected and returned to blood system by me of a series of tubules known as lymph vessels or lymphatics.

The fluid inside the lymphatics is called lymph. The lymphatic system consists of a complex network of thin walled ducts (lymphatic vessels), filtering bodies (lymph nodes) and a large number of lymphocytic cell concentrations in various lymphoid organism.

The lymphatic vessels have smooth walls that run parallel to the blood vessels, in the skin, along the respiratory and digestive tracts. These vessels serve as return ducts for the fluids that are continually diffusing out of the blood capillaries into the body tissues.

Lymph fluid must pass through the lymph nodes before it is returned to the blood. The lymph nodes that filter the fluid from the lymphatic vessels of the skin are highly concentrated in the neck, inguinal, axillaries, respiratory and digestive tracts.

The lymph fluid flowing out of the lymph nodes flow into large collecting duct which finally drains into larger veins that runs beneath the collar bone, the subclavian vein and is emptied into the bloodstream. The narrow passages in the lymph nodes are the sinusoids that are lined with macrophages.

The lymph nodes successfully prevent the invading microorganisms from reaching the bloodstream. Cells found in the lymphatics are lymphocytes. Lymphocytes collected in the lymphatic fluid are carried via the arterial blood and are recycled back to the lymph. Fats are absorbed through lymph in the lacteals present in the villi of the intestinal wall.

Question 23.
What are the heart sounds? When and how are these sounds produced?
Answer:
Rhythmic contraction and expansion of the heart are called heartbeat. The contraction of the heart is called systole and the relaxation of the heart is called diastole. The heart normally beats 70-72 times per minute in a human adult. During each cardiac cycle, two sounds are produced that can be heard through a stethoscope.

The first heart sound (lub) is associated with the closure of the tricuspid and bicuspid valves whereas the Second heart sound (dub) is associated with the closure of the semilunar valves. These sounds are of clinical diagnostic significance. An increased heart rate is called tachycardia and decreased heart rate is called bradycardia.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 24.
Select the correct biological term.
Lymphocytes, red cells, leukocytes, plasma, erythrocytes, white cells, hemoglobin, phagocyte, platelets, blood clot.
Answer:

a. Disc-shaped cells which are concave on both sides. Red cells
b. Most of these have a large bilobed nucleus Leucocytes
c. Enable red cells to transport blood. Haemoglobin
d. The liquid part of the blood Plasma
e. Most of them move and change shape like an amoeba Leucocytes
f. Consists of water and important dissolved substances. Plasma
g. Destroyed in the liver and spleen after circulating in the blood for four months. Red cells
h. The substances which give red cells their colour Haemoglobin
i. Another name for red cells Erythrocytes
j. Blood that has been changing to jelly Blood clot
k. A word that means cell eater Phagocytes
l. Cells without nucleus Red cells
m. White cells made in the lymphatic tissue Lymphocytes
n. Blocks wound and prevent excessive bleeding. Blood clot
o. Fragment of cells which are made in the bone marrows Platelets
p. Another name for white blood cells. Leucocytes
q. Slowly releases oxygen to blood cells. Haemoglobin
r. Their function is to help blood clots in wounds. Platelets

Question 25.
Select the correct biological term. Cardiac muscle, atria, tricuspid systole, auricles, arteries, diastole, ventricles, bicuspid valve, pulmonary artery, cardiac cycle, semilunar valve, veins, pulmonary vein, capillaries, vena cava, aorta.
Answer:

a. The main artery’ of the blood. Dorsal aorta
b. Valves between the left atrium and ventricle. Bicuspid valve
c. Technical name for relaxation of the heart. Diastole
d. Another name for atria. Auricle
e. The main vein. Vena cava
f. Vessels which carry blood away from the heart. Aorta
g.Two names for the upper chambers of the heart. Auricle
h. Thick-walled chambers of the heart. Ventricle
I. Carries blood from the heart to the lungs. Pulmonary artery
j. Takes about 0.8 sec to complete. Cardiac cycle
k. Valves situated at the point where blood flows out of the heart. Semilunar valve
l. Vessels which carry blood towards the heart. Vein
m. Carries blood from the lungs to the heart. Pulmonary vein
n. The two lower chambers of the heart. Ventricle
o. Prevent blood from re-entering the ventricles after entering the aorta. Semilunar valve
P. Technical name for one heartbeat. Cardiac cycle
q. Valves between right atrium and ventricles. Tricuspid valve
r. The technical name for the contraction of the heart. Systole
s. Very narrow blood vessels. Capillaries

Question 26.
Name and Label the given diagrams to show A, B, C, D, E, F, and G.
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation 2

Part II

11th Bio Zoology Guide Body Fluids and Circulation Additional Important Questions and Answers

I. Choose The Best Options

Question 1.
Which of the following is not the function of circulatory system?
(a) Transport of respiratory gases
(b) Carrying of digested food materials
(c) Transport of hormones to target organism
(d) Removal of nitrogenous wastes from the body
Answer:
(d) Removal of nitrogenous wastes from the body

Question 2.
Find out the wrong statement.
a. The density of protein in tissue fluid is lesser than plasma
b. Blood is a fluid connective tissue
c. The amount of blood present in the 70 kg man is 5 litre
d. The plasma protein albumin provided immunity.
Answer:
d. The plasma protein albumin provided immunity.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 3.
What is the function of albumin?
(a) Transport of hormones
(b) Blood clothing
(c) Maintenance of osmotic pressure
(d) Immunity
Answer:
(c) Maintenance of osmotic pressure

Question 4.
Which of the following is rich in urea?
a. Hepatic vein
b. Splenic vein
c. Pancreatic vein
d. Pulmonary vein
Answer:
a. Hepatic vein

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 5.
The red colour of the RBC is due to the presence of a respiratory pigment ……………
(a) Haemoerythrin
(b) Haemoglobin
(c) Haemocyanin
(d) Chlorocronin
Answer:
(b) Haemoglobin

Question 6.
Which is a heterophil?
a. Neutrophils
b. Eosinophil
c. Basophil
d. Monocytes
Answer:
a. Neutrophils

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 7.
What is hematocrit/packed cells volume?
(a) The ratio of WBCs to blood plasma
(b) The ratio of RBCs to blood plasma
(c) The ratio of platelets to blood plasma
(d) The ratio of plasma and blood cells
Answer:
(b) The ratio of RBCs to blood plasma

Question 8.
Name the blood cell secreted by megakaryocytes?
a. Red blood cells
b. White blood cells
c. Platelets
d. None of the above
a. I – d, II – c, III – b, IV – a
b. I – a, II – d, III – b, IV – c
c. I – a, II – d, III – b, IV – c
d. I – d, II – c, III – a, IV – b
Answer:
c. I – a, II – d, III – b, IV – c

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 10.
Name the protein which is similar to the protein present in the red blood cells of Rhesus Monkey.
a. D – antigen
b. A – antigen
c. B – antigen
d. A, B – antigen
Answer:
a. D – antigen

Question 11.
Confirm A: Red blood cell contains more hemoglobin
Reason B: There are no cell organelles in the red blood cells.
a. A – True, B – False
b. A – True, B – True
c. A – False, B – True
d. A – False, B – False
Answer:
b. A – True, B – True

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 12.
‘A’ blood group has ………………….. antigen and …………………. antibody
(a) A, anti B
(b) AB, no antibodies
(c) No antigen, anti A, Anti B
(d) B, Anti A
Answer:
(d) B, Anti A

Question 13.
Name the white blood cells present in lymph?
a. Lymphocytes
b. Monocytes
c. Neutrophils
d. Basophils
Answer:
a. Lymphocytes

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 14.
Name the layer which is not seen in capillaries
a. Tunica intima
b. Tunica media
c. Tunica external
d. Tunica internal
Answer:
b. Tunica media

Question 15.
How much time is taken for a single cardiac cycle?
a. 0.7 secs
b. 0.8 secs
c. 0.6 secs
d. 10.9 secs
Answer:
b. 0.8 secs

Question 16.
Pulmonary veins carry ………………. blood from lungs to ……………….
(a) Oxygenated, right auricle
(b) Deoxygenated, right auricle
(c) Deoxygenated, left auricle
(d) Oxygenated, left auricle
Answer:
(c) Deoxygenated, left auricle

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 17.
The slow excitation of the ‘QRS’ wave indicates ………………………….. defect.
a. Inflammation of ventricle
b. Defects in bicuspid valve
c. Block in the coronary artery
d. Defects in the atrioventricular node
Answer:
a. Inflammation of ventricle

Question 18.
Who has explained first about blood circulation?
a. Raymond deviessens
b. William Harvey
c. Robert William
d. James Elam
Answer:
b. William Harvey

Question 19.
What is the normal blood pressure of a man?
a. 120/90 mm Hg
b. 120/80 mm Hg
c. 120 /80 mm Hg
d. 130/80 mm Hg
Answer:
c. 120 /80 mm Hg

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 20.
Which of the following is the cause of a stroke?
a. Rupture of blood vessels in the brain
b. A clot in the blood vessels of brain
c. Deposition in the blood vessels of the brain
d. All the above
Answer:
d. All the above

Question 21.
Does ischemic heart disease indicate?
a. Myocardial infarction
b. Rheumatoid heart disease
c. Angino pectoralis
d. Stroke
Answer:
a. Myocardial infarction

Question 22.
Which hormone increases the heartbeat?
(a) Acetylcholine
(b) Gastrin
(d) Epinephrine
(d) Oxytocin
Answer:
(c) Epinephrine

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 23.
Match the following and find the correct answer?
I. Erythropoietin – a. Agglutinization
II. Haematocrit – b. It takes an important role in the inflammation of body tissues
III. Heparin – c. Finding the ratio between blood plasma and red blood cells.
IV. Antigen – d. It stimulates the synthesis of RBCs in the bone marrow.
a. I-d, II-c, III – b, IV-a
b. I – a, II – b, III – c, IV – d
c. I – a, II – c, III – d, IV – b
d. I – d, II – c, III – b, IV – a
Answer:
a. I-d, II-c, III – b, IV-a

Question 24.
Note the given diagram and find out the correct answers.
a. T wave represents the repolarisation of auricle
b. The ‘P’ wave represents the functions of auricle
c. Te ‘Q’ wave represents the depolarization of ventricular septum
d. ‘R’ and ‘S’ wave represents depolarization of auricle
Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation 3
Answer:
b. The ‘P’ wave represents the functions of the auricle

(2 marks)

II. Very Short Questions

Question 1.
What are the types of body fluids?
Answer:
The intra-cellular fluid present inside the cells and the extracellular fluid present outside the cells are the two types of body fluids.

Question 2.
What is meant by interstitial fluid or tissue fluid?
Answer:
A fluid that surrounds the cell is known as interstitial fluid.
(Eg.) Plasma, Lymph

Question 3.
Give short notes on blood?
Answer:

  • Blood is the most common body fluid that transports substances from one part of the body to the other. It is known as fluid connective; tissue.
    • The plasma constitutes 55% of total blood volume.
  • The average blood volume is about 5000 mZ (51) is an adult weighing 70 kg.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 4.
What are the components of blood?
Answer:

  1. Red blood cells
  2. White blood cells.
  3. Platelets

Question 5.
Why is the spleen considered a graveyard of red blood cells?
Answer:

  • The average life span of red cells is 120 days.
  • After 120 days the red cells are destroyed in the spleen. Hence the spleen said to be a graveyard of RBCs.

Question 6.
What is hematocrit?
Answer:
The ratio of red blood cells to blood plasma is expressed as hematocrit (packed cell volume).

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 7.
What are the types of lymphocytes? What are its uses?
Answer:

  • B – lymphocytes – Produces antibodies
  • T – lymphocytes – Involves in cell-mediated immunity.

Question 8.
Classify the monocytes based on its location?
Answer:

Location Name
1. Central nervous system Microglia
2. Liver sinuses Kupffer cells
3. Lungs Macrophages of alveolei

Question 9.
What are the types of ‘ABO’ blood groups?
Answer:

  • A -blood group
  • B – blood group
  • AB – blood group
  • O- blood group

Question 10.
What is meant by alleleic genes?
Answer:
The gene that regulates the synthesis of A, B and O blood groups in ‘ABO’ type.

Question 11.
What are agglutinogens? What is it’s composition?
Answer:
Antigens present on the surface of RBCs are called agglutinogens.

Composition:
Sucrose, D – galactose, N – acetyl glucosamine, 11 terminal amino acids

Question 12.
What are the steps to be taken to prevent erythroblastosis f oetalis?
Answer:
After the first delivery if the first child is the Rh+ve, we should give anti D – antibodies -Rhocum to the
Rh-ve mother.

Question 13.
What is serum?
Answer:
Plasma without fibrinogen is called serum.

Question 14.
What is an anticoagulant substance? Where is it synthesized?
Answer:
Heparin is an anti-coagulant substance. It is synthesized in the mast cells.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 15.
What are the layers of blood vessels
Answer:

  1. Tunica externa – Outer layer
  2. Tunica media – Mid layer
  3. Tunica indima – Inner layer

Question 16.
Give notes on capillaries.
Answer:

  • There is no tunica media in the capillaries
  • It is the site for the exchange of materials between blood and tissues.
  • The blood volume is high but the flow of blood is low.
  • The walls of the capillaries are guarded by semilunar valves.
  • The oxygenated and deoxygenated blood is present in the capillaries.

Question 17.
What is meant by single circulation?
Answer:

  • Single circulation is seen in fishes. There is only one auricle and ventricle in the heart of fishes.
  • The blood flows from heart to gills there it gets oxygenated and supplies to the organ and then returns to the heart.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 18.
What is meant by incomplete double circulation?
Answer:
Reptiles have an incompletely divided ventricle. The oxygenated and deoxygenated blood is mixed here. Hence it is known as incomplete double circulation.

Question 19.
What is meant by complete double circulation?
Answer:

  • There are well divided 2 auricle and 2 ventricles in the heart of birds, crocodiles and mammals.
  • The oxygenated and deoxygenated blood is completely separated.
  • The pulmonary and systemic circulation is well defined.

Question 20.
Differentiate the tachycardia and bradycardia?
Answer:

Tachycardia
1. The rate of heartbeat increases
Bradycardia
The rate of heartbeat decreases.

Question 21.
What is meant by cardiac output?
Answer:
The amount of blood pumped out by each ventricle per minute is called the cardiac output.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 22.
What is meant by pulse or pulse rate?
Answer:
The rate of heartbeat per minute is called a pulse.

Question 23.
What is meant by pulse pressure?
Answer:
Pulse pressure: Systolic pressure -diastolic pressure.

Question 24.
What is meant by stroke volume?
Answer:
Stroke volume is the volume of blood pumped out by one ventricle with each beat.
CO = HR x SV

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 25.
When will the stroke volume double?
Answer:

  • During vigorous exercise, SV may double as a result of venous return.
  • The amount of blood pumps out of the ventricle is also increased.

Question 26.
What is meant by mean arterial pressure?
Answer:
Mean arterial pressure is a function of cardiac output and resistance in the arterioles.

Question 27.
What is the baroreceptor reflex?
Answer:
The primary reflex pathway for homeostatic control of mean arterial pressure is the baroreceptor reflex.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 28.
What is meant by orthostatic hypotension?
Answer:
When we are lying flat the gravitational force is evenly distributed. When you stand up gravity causes blood to pool in the lower extremities. The decrease in blood pressure upon standing is known as orthostatic hypotension.

Question 29.
What is myogenic heart?
Answer:
The heartbeat of man is originated from the cardiac muscles. Hence human heart is a myogenic heart.

Question 30.
Tabulate the cardiac diseases?
Answer:

Diseases Defects
1. Coronary heart disease When the coronary arteries are blocked the amount of blood goes to heart muscles decreases leads to oxygen and nutrient deficiency.
2. Vascular diseases Infection in the arteries veins and lymphatic glands
3. Aorta disease The wall of the aorta weakened and bulges to form a balloon-like sac aneurysm.
4. Pericarditis Inflammation in the layers of the pericardium
5. Cardio myopathy An abnormally thick heart muscle causing the heart to pump weaker than normal and leads to heart failure.
6. Heart valve disease One or more of the heart valves does not work.
7. Heart failure The heart cannot pump as powerfully as it need to in order to supply like body with 0, and nutrients carrying heart muscles to overwork and weaker.
8. Arrhythmia The heart beats irregularly

Question 31.
What is edema?
Answer:
The concentration of proteins in the blood becomes much lower than usual leads to the accumulation of fluid.

Question 32.
The walls of arteries nearer to the heart are more elastic than the arteries away from the heart? Why?
Answer:

  • When the heart contracts the blood is pushed into the artery hence the pressure in the arteries increases.
  • To withstand the pressure the artery walls nearer to the heart are more elastic and hence they relax and reduce the pressure.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 33.
How is the blood needed for the skeletal muscle during exercise compensated?
Answer:

  • During exercise, more blood is needed for skeletal muscle.
  • Hence the blood is diverted from the digestive system to skeletal muscle.

Question 34.
Define Laplace law? What do you infer from this?
Answer:

  • It states that the tension in the walls of the blood vessel is proportional to the blood pressure and vessel radius.
  • This law is used to understand the structure and function of blood vessels and the heart.

Question 35.
When blood volume drops down abruptly? What happens to the stroke volume?
Answer:
When there is a drop in blood volume the blood flows to the heart decreases hence the blood coming out of the heart during contraction decreases. (Stroke volume decreases)

(3 marks)

III. Short Questions

Question 1.
List the characteristics of the circulatory system?
Answer:

  • Oxygen and carbon dioxide are exchanged in the luiìgs and tissues.
  • Nutrients are taken from the digestive system and are carried to the liver and through blood taken to all parts of the body.
  • Wastes from the tissues are carried by the blood and finally removed by the kidneys.
  • The hormones are transported to their target organs.
  • Circulatory system helps to maintain the homeostasis of the body fluids and body temperature.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation 4

Question 2.
Explain the role of the Rh factor?
Answer:
Rh factor is a protein (D antigen) present on the surface of the red blood cells in the majority (80%) of hum. This protein is similar to the protein present in Rhesus monkey, hence the term Rh. Individuals who carry the antigen D on the surface of the red blood cells are Rh+ (Rh-positive) and the individuals who do not carry antigen D, are Rh (Rh-negative). Rh factor compatibility is also checked before blood transfusion.

When a pregnant woman is Rh+ and the foetus is Rh+ incompatibility (mismatch) is observed. During the first pregnancy, the Rh antigens of the foetus do not get exposed to the mother’s blood as both their blood are separated by the placenta. However, small amount of the foetal antigen becomes exposed to the mother’s blood during the birth of the first child.

The mother’s blood starts to synthesize D antibodies. But during subsequent pregnancies, the Rh antibodies from the mother (Rh) enters the foetal circulation and destroys the foetal RBCs. This becomes fatal to the foetus because the child suffers from anaemia and jaundice. This condition is called erythroblastosis foetalis. This condition can be avoided by administration of anti D antibodies (Rhocum) to the mother immediately after the first childbirth.

Question 3.
Describe red blood cells?
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation 5

  1. Red blood cells are abundant than other blood cells. There are about 5 – 5.5 million RBC mm of blood in a healthy man and 4.5 – 5 million RBC mm” in healthy women.
  2. The red colour of the RBC is due to the respiratory pigment haemoglobin and it involves in the transport of respiratory gases.
  3. The biconcave-shaped RBC s increase the surface area.
  4. The RBCs are devoid of nucleus mitochondria ribosomes and endoplasmic reticulum.
  5. The average life span of RBC is about 120 days after which they are destroyed in the spleen.
  6. RBCs are synthesized in the bone marrow.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 4.
Give notes on platelets?
Answer:

  • Platelets are known as thrombocytes.
  • They are synthesized by the megakaryocytes of bone marrow.
  • They are devoid of a nucleus.
  • Blood normally contains 150000 – 350000 platelets mm3 of blood.
  • They are involved in blood coagulation.
  • The reduction in platelet number can lead to clotting disorders leads to excessive loss of blood from the body.

Question 5.
Arrange the blood groups, their antigens and antibodies and tabulate them.
Answer:

Blood group Agglutiongens (antigens) on the RBC Agglutinin antibodies in the plasma
A A Anti B
B B Anti A
AB AB No antibodies
O No antigens Anti A and Anti B

Question 6.
What are anastomoses?
Answer:

  • These are connections of one blood vessel with another blood vessel.
  • They provide an alternate route of blood flow if the original blood vessel is blocked.
  • Arteries in the joints contain numerous anastomoses. This allows blood to flow freely even if one of the arteries closes during bending of the joints.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 7.
Write notes on coronary blood vessels.
Answer:

  • Blood vessels that supply blood to the cardiac muscles with all nutrients and remove wastes are the coronary artries and veins.
  • Heart muscle is supplied by two arteries namely the right and left coronary arteries.
  • These arteries are the first branch of the aorta.
  • These arteries usually surround the heart in the manner of a crown hence called the coronary artery.
  • Right ventricle and posterior portion of the left ventricle are supplied by the right coronary artery.
  • Anterior and lateral part of the left ventricle is supplied by the left coronary arteries.

Question 8.
Give notes on the heartbeat.
Answer:

  1. Rhythmic contraction and expansion of heart is called heartbeat. The contraction of the heart is called systole and the relaxation of the heart is called diastole.
  2. The heart normally beats 70 – 72 times per min in a normal adult. Lub and dub sound is produced. These are heart sounds.
  3. The sound lub is associated with the closure of the tricuspid and bicuspid and the dub sound is associated with the closure of the semilunar valves.
  4. The heart sounds can be heard through a stethoscope.
  5. These sounds are of clinical diagnostic significance.
  6. An increased heart rate is called tachycardia and decreased heart rate is called bradycardia.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 9.
What is blood pressure?
Answer:

  • Blood pressure is the pressure exerted on the surface of blood vessels by the blood.
  • This pressure circulates the blood through arteries veins and capillaries.
  • There are 2 types of pressure the systolic pressure and diastolic pressure.
  • Systolic pressure is the pressure in the arteries as the chambers of the heart contract.
  • Diastolic pressure is the pressure in the arteries when the heart chambers relax
  • Blood pressure is measured using a sphygmomanometer.
  • Normal blood pressure in man is about 120 / 80 mm Hg.

Question 10.
What is single circulation and what is double circulation?
Answer:
Single circulation:

  • The blood circulates once through heart and supplies blood to all the parts of the body. This is single circulation.
  • There is systemic and pulmonary circulation. (Eg.) The two-chambered heart of fishes.

Double circulation:
There are two types of circulation.
Systemic circulation:

  • The oxygenated blood entering the aorta from the left ventricle is carried by a network of arteries to the tissues.
  • The deoxygenated blood from the tissue is collected and emptied into the right atrium.

Pulmonary circulation:
The blood from right ventricle is taken to the lungs by the pulmonary artery and the oxygenated blood from the lungs is emptied into the left auricle by the pulmonary vein.

Question 11.
Why the pressure in the blood vessels nearer to the alveolei of lung is low and the pressure of arteries nearer to the heart is high?
Answer:

  • The alveoli are very thin. Hence exchange of gases are taking place easily.
  • If the pressure of the blood vessels of alveoli increases the blood vessels will damage and there is collection of tissue fluid

Question 12.
Explain heart failure or myocardial infarction?
Answer:

  • This heart failure is due to a decrease in cardiac muscle contractility.
  • When the blood supply to the heart muscle is remarkably reduced it leads to the death of the muscle fibres.
  • The blood clot or thrombosis blocks the blood supply to the heart and weakens the muscle fibres.
  • It is also called Ischemic heart disease due to a lack of oxygen supply to the heart muscles.
  • If this persists it leads to chest pain or angina.
  • Prolonged angina leads to death of the heart muscle resulting in heart failure.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 13.
What is cardiopulmonary resuscitation?
Answer:
1. Cardiopulmonary resuscitation is a life-saving procedure that is done at the time of emergency conditions such as when a person’s breath on heartbeat has stopped abruptly in case of drowning electric shock or heart attack.

2. CPR includes rescue of breath which is achieved by mouth to mouth breathing to deliver oxygen to the victim’s lungs by external chest compression which helps to circulate blood to the vital organs.

3. CPR must be performed within 4 to 6 minutes. Brief electric shock is given to the heart to recover the function of the heart (defibrillation).

Question 14.
What is meant by varicose veins?
Answer:

  • The veins are so dilated that the valves prevent the backflow of blood.
  • The veins lose their elasticity and become congested.
  • Common sites are legs rectal anal regions, and spermatic cords.

Question 15.
What is embolism?
Answer:

  • It is the obstruction of the blood vessel.
  • It is due to the abnormal mass of materials such as fragments of the blood clot.
  • If embolus occurs in the lungs coronary artery or liver that leads to death.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 16.
Write notes on Rheumatoid heart disease?
Answer:

  • Rheumatic fever is an auto immense disease.
  • It is due to the streptococcal infection in the throat.
  • The fever occurs 2-4 weeks after the infection.
  • The antibodies developed to combat the infection cause damage to the heart.
  • The symptoms include fibrous nodules on the mitral valve.
  • Fibrosis of the connective tissue and accumulation of fluid in the pericardial cavity.

Question 17.
Write notes on stroke and Angina pectoris?
Answer:
Stroke:
Stroke is a condition when the blood vessels in the brain bursts or when there is a block in the artery that supplies the brain. The part of the brain tissue that is supplied by this damaged artery dies due to lack of oxygen, (cerebral infarction)

Angina Pectoris:
If Atheroma may partially block the coronary artery and reduce the blood supply to the heart. As a result, there is tightness or choking with difficulty in breathing.
This leads to angina or chest pain. It lasts for a short duration of time.
reduces the blood flow.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 19.
Give short notes on heart transplantation?
Answer:

  • The first heart transplantation surgery was performed by South African professor – Christian Bernard in the year 1959.
  • He has done heart transplantation operation on December 3rd, 1967 Inkrute shour hospital at Capetown.
  • In India, in 1994 at AIMS hospital on August 3rd Dr. Anangipalli Venu Gopal has performed heart transplantation surgery.

Question 20.
What is an aneurysm?
Answer:

  • The weekened regions of the wall of the artery orvein bulge to forma baloon like sac. This is called aneurysm.
  • Unruptured aneurysm may exert pressure on the adjacent tissues or may burst causing massive hemorrhage.

( 5 marks)

V. Essay Questions

Question 1.
Describe white blood cells.
Answer:

  • White blood cells are colourless amoeboid nucleated cells devoid of hemoglobin and hence colourless.
  • 6000 – 8000 per cubic mm of WBC s are seen in the blood. WBCs are synthesized in the bone marrow these are of two types.
  • Granulocytes and agranolocytes.

I Granulocytes:
a) Neutrophils:

  • They are also called heterophils. Hence the nucleus has 3-4 lobes they are called polymorphonuclear.
  • This constitutes about 60 – 65 % of the total WBC.

b) Eosinophils:

  • They have a bilobed nucleus.
    Eosinophils Basophils Neutrophils
  • It constitutes about 2 – 3 % of total WBCs.
  • Their number increases during allergic reactions.

c) Basophils:

  • They are less numerous than any other type of WBCs constituting 0.5 % -1 % of total WBCs.
  • The nucleus is large and has granules in the cytoplasm.
  • They secrete heparin serotonin and histamines.

II A granulocytes:
a) Lymphocytes:

  • They are secreted in the lymph gland and spleen.
  • Lymphocytes constitute 28% of WBCs. They have large nucleus and small amount of cytoplasm.
  • The two types of lymphocytes are B and T cells.
  • B cells produce antibodies to neutralize the harmful effects of foreign substances. T cells are involved in cell-mediated immunity.

b) Monocytes:

  • They are phagocytic cells. They have kidney-shaped nucleus. They constitute 1 – 3 % of the total WBCs.
  • The macrophages of the central nervous system are the microglia and in the liver they are called “Kupffer cells” and in the pulmonary region they are the alveolar macrophages.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 2.
Explain cardiac output in a man?
Answer:
The amount of blood pumped out by each ventricle per minute is called cardiac output (CO). It is a product of heart rate (HR) and stroke volume (SV). Heart rate or pulse is the number of beats per minute. Pulse pressure = systolic pressure – diastolic pressure. Stroke volume (SV) is the volume of blood pumped out by one ventricle with each beat. SV depends on ventricular contraction.

CO = HR x SV. SV represents the difference between EDV (amount of blood that collects in a ventricle during diastole) and ESV (volume of blood remaining in the ventricle after contraction). SV = EDV – ESV. According to Frank-Starling law of the heart, the critical factor controlling SV is the degree to which the cardiac muscle cells are stretched just before they contract.

The most important factor stretching cardiac muscle is the amount of blood returning to the heart and distending its ventricles, venous return.
During vigorous exercise, SV may double as a result of venous return.

Heart’s pumping action normally maintains a balance between cardiac output and venous return. Because the heart is a double pump, each side can fail independently of the other. If the left side of the heart fails, it results in pulmonary congestion and if the right side fails, it results in peripheral congestion. Frank – Starling effect protects the heart from abnormal increase in blood volume.

Question 3.
What is the coagulation of blood?
Answer:
The mechanism by which excessive blood loss is prevented by the formation of clot is called blood coagulation.

  • The clotting process begins when the endothelium of the blood vessel is damaged and the connective tissue in its wall is exposed to the blood.
  • Platelets adhere to collagen fibres in the connective tissue and release blood clotting factors.
  • The blood clotting factors with platelets form the platelet plug which provides emergency protection against blood loss.
  • Clotting factors released from the clumbed platelet mix with clotting factors in the plasma.
  • The inactivated prothrombin is converted into active thrombin in the presence of calcium and vitamin K.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation 6

Thrombin converts soluble fibrinogen into insoluble fibrin in plasma Fibrinogen Thrombin Fibrin
Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation 7

The threads of fibers become interlinked into a patch that traps blood cell and seals the injured vessel and prevents blood loss.

Question 4.
Give an account of the composition of lymph and explains its significances?
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation 8

  • About 90% of fluid that leaks from capillaries seeps back into the capillaries and the remaining 10% is collected and returned to the blood system by means of lymph vessel.
  • The fluid inside the lymphatics is called lymph.

Lymphatic system:

  • The lymphatic system consists of a complex network of thin-walled ducts having group of immune response cells.
  • The lymphatic vessels have smooth walls that run parallel to the blood vessels in the skin along the respiratory and digestive tracts.
  • These vessels serve as return ducts for the fluids that are continually diffusing out of the blood capillaries into the body tissues.
  • The lymphatic nodes arc concentrated in the neck ingunial axillaries respiratory and digestive tracts.
  • The lymph fluid flowing out of the lymph nodes flows into large collecting ducts which finally drains into larger veins that run beneath the collar bone the subclavian vein and is emptied into the bloodstream.
  • The lymph nodes contain macrophage cells and they prevent the invading microorganisms from reaching the bloodstream. Cells found in the lymphatics are lymphocytes.
  • Fats are absorbed through lymph in the lacteals present in the villi of the intestinal wall

Question 5.
Describe the structure of the heart with a diagram?
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation 9

  • The structure of the human heart was described by Raymond devises in 1706.
  • It is situated in the thoracic cavity and its apex portion is slightly tilted towards left. It weighs about 300 g in a adult. The size of our heart is roughly equal to a closed fist.
  • Heart is divided into four chambers upper two auricles and lower two ventricles.
  • The walls of the ventricles are thicker than the auricle.
  • The heart is covered with pericardium. The pericardial space is filled with pericardial fluid.
  • The heart wall is made up of three layers. The outer epicardium middle myocardium the inner endocardium.
  • The two auricles are separated by inter auricular septum and the two ventricles are separated by interventricular septum.
  • Tricuspid valve is present in between the opening of right auricle and right ventricle and the bicuspid valve is present in between the opening of left auricle and left ventricle.
  • From the right ventricle arises pulmonary artery and from the left ventricle arises the dorsal aorta.
  • The semilunar valve is present at the beginning of these arteries.
  • The deoxygenated blood from all the parts of body reaches left auricle through superior and inferior venacava.
  • The oxygenated blood reaches the left auricle through four pulmonary vein.

Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation

Question 6.
Describe the functioning of heart with a diagram or Describe about the cardiac cycle?
Answer:
Samacheer Kalvi 11th Bio Zoology Guide Chapter 7 Body Fluids and Circulation 10
The events that occur at the beginning of heart beat and lasts until the beginning of next beat is called cardiac cycle. It lasts for 0.8 seconds.

Phase I:
Ventricular diastole – During this phase the blood pressure increases AV valves are opened and the semilunar valves are closed. Blood flows from the auricles into the ventricles passively.

Phase II:
During atrial systole the ventricle is in relaxed position. The contraction of the auricles pushes maximum volume of blood to the ventricles.
The end-diastolic volume is related to the length of the cardiac muscle fibre. More the muscle is stretched greater the EDV and the stroke volume.

Phase III:
Ventricular systole – During this phase the ventricular pressure increases and the AV value closes.
The blood is pumped from the ventricles into the aorta.

Phase IV:
Ventricular systole – During this phase the ventricular pressure increases that forces semi lunar valve to open.
Blood is ejected out of the ventricles without back flow of blood.
This point is the end of systolic volume.

Phase V:
Ventricular diastole – The ventricles begins to relax pressure in the arteries exceeds ventricular pressure resulting in the closure of semilunar valves.
The heart returns to phase I of the cardiac cycle.

Question 7.
Explain Cardio Pulmonary Resuscitation (CPR)?
Answer:
In 1956, James Elam and Peter Safar were the first to use mouth-to-mouth resuscitation. CPR is a life-saving procedure that is done at the time of emergency conditions such as when a person’s breath or heart beat has stopped abruptly in case of drowning, electric shock or heart attack.

CPR includes rescue of breath, which is achieved by mouth to mouth breathing, to deliver oxygen to the victim’s lungs by external chest compressions which helps to circulate blood to the vital organiser.

CPR must be performed within 4 to 6 minutes after cessation of breath to prevent brain damage or death. Along with CPR, defibrillation is also done. Defibrillation me a brief electric shock is given to the heart to recover the function of the heart.

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