NCERT Exemplars: Body Fluids & Circulation - 1 | Biology Class 11 - NEET PDF Download

MULTIPLE CHOICE QUESTIONS

Q.1. Which of the following cells does not exhibit phagocytic activity
(a) Monocyte
(b) Neutrophil
(c) Basophil
(d) Macrophage
Ans. (c)
Solution.
Basophils secrete histamine, serotonin, heparin, etc., and are involved in inflammatory reactions.

Q.2. One of the common symptoms observed in people infected with Dengue fever is
(a) Significant decrease in RBC count
(b) Significant decrease in WBC count
(c) Significant decrease in platelets count
(d) Significant increase in platelets count
Ans. (c)
Solution.
One of the common symptoms observed in people infected with Dengue fever is significant decrease in platelets count.

Q.3. Which among the followings is correct during each cardiac cycle?
(a) The volume of blood pumped out by the Rt and Lt ventricles is same.
(b) The volume of blood pumped out by the Rt and Lt ventricles is different
(c) The volume of blood received by each atrium is different
(d) The volume of blood received by the aorta and pulmonary artery is different
Ans. (a)

Q.4. Cardiac activity could be moderated by the autonomous neural system.
Tick the correct answer:
(a) The parasympathetic system stimulates heart rate and stroke volume
(b) The sympathetic system stimulates heart rate and stroke volume
(c) The parasympathetic system decreases the heart rate but increases stroke volume
(d) The sympathetic system decreases the heart rate but increases stroke volume
Ans. (b)
Solution.
A special neural centre in the medulla oblongata can moderate the cardiac function through autonomic nervous system (ANS). Neural signals through the sympathetic nerves (part of ANS) can increase the rate of heart beat, the strength of ventricular contraction and thereby the cardiac output. On the other hand, parasympathetic neural signals (another component of ANS) decrease the rate of heart beat, speed of conduction of action potential and thereby the cardiac output.

Q.5. Mark the pair of substances among the following which is essential for coagulation of blood.
(a) Heparin and calcium ions
(b) Calcium ions and platelet factors
(c) Oxalates and citrates
(d) Platelet factors and heparin
Ans. (b)
Solution.
Calcium ions and platelet factors are essential for coagulation of blood.

Q.6. ECG depicts the depolarisation and repolarisation processes during the cardiac cycle. In the ECG of a normal healthy individual one of the following waves is not represented.
(a) Depolarisation of atria
(b) Repolarisation of atria
(c) Depolarisation of ventricles
(d) Repolarisation of ventricles
Ans. (b)
Solution.
ECG depicts the depolarisation and repolarisation processes during the cardiac cycle. In the ECG of a normal healthy individual repolarisation of atria is not represented.

Q.7. Which one of the following types of cells lack nucleus in humans?
(a) Erythrocytes
(b) Neutrophils
(c) Eosinophils
(d) Monocytes
Ans. (a and d)
Solution.
RBCs or erythrocytes lack nucleus in humans.

Q.8. Which one of the following blood cells is involved in antibody production.
(a) B-Lymphocytes
(b) T-Lymphocytes
(c) RBC
(d) Neutrophils
Ans. (a)
Solution.
B-lymphocytes cells are involved in antibody production.

Q.9. The cardiac impulse is initiated and conducted further upto ventricle. The correct sequence of conduction of impulse is

Ans. (c)

Q.10. The cells involved in inflammatory reactions are
(a) Basophils
(b) Neutrophils
(c) Eosinophils
(d) Lymphocytes
Ans. (A)
Solution.

The blood cells are of three major types they are erythrocytes(RBC), leucocytes(WBC) and platelets. Two main categories of WBCs are granulocytes and agranulocytes. Neutrophils, eosinophils, and basophils are different types of granulocytes, while lymphocytes and monocytes are the agranulocytes. When basophils are encountered with allergin they release histamine which causes increased blood flow to damaged tissues, resulting in swelling and inflammation. Hence blood cells involved in inflammatory reactions are Basophils.

So, the correct answer is 'Basophils'.

Q.11. The second heart sound (dubb) is associated with the closure of
(a) Tricuspid valve
(b) Semilunar valves
(c) Bicuspid valve
(d) Tricuspid and bicuspid valves.
Ans. (b)
Solution.
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.

Q.12. Which of the following correctly explains a phase/ event in cardiac cycle in a standard electrocardiogram?
(a) QRS complex indicates atrial contraction.
(b) QRS complex indicates ventricular contraction.
(c) Time between S and T represents atrial systole.
(d) P-wave indicates beginning of ventricular contraction.
Ans. (b)
Solution.
• P-wave—Atrial depolarisation (atrial systole/contraction)
• QRS complex—Ventricular depolarisation (ventricular systole/contraction)
• T-wave—Ventricular repolarisation (ventricular relaxation)

Q.13. Which of the following statements is incorrect?
(a) A person of ‘O’ blood group has anti ‘A’ and anti ‘B’ antibodies in his blood plasma.
(b) A person of ‘B’ blood group can’t donate blood to a person of ‘A’ blood group.
(c) Blood group is designated on the basis of the presence of antibodies in the blood plasma.
(d) A person of AB blood group is universal recipient.
Ans. (c)
Solution.
Blood group is designated on the basis of the antigen is present on the RBCs surface

Q.14. What would be the cardiac output of a person having 72 heart beats per minute and a stroke volume of 50 ml?
(a) 360 mL
(b) 3600 mL
(c) 7200 mL
(d) 5000 mL
Ans. (b)
Solution.
Cardiac output = Stroke volume x Heart rate = 50 x 72 = 3600 mL/min

Q.15. Match the terms given under Column ‘A’ with their functions given under Column ‘B’ and select the answer from the options given below:

Options:
(a) A-ii, B-i, C-iii, D-iv
(b) A-iii, B-i, C-iv, D-ii
(c) A-iii, B-i, C-iii, D-iv
(d) A-ii, B-i, C-iii, D-iv
Ans. (b)
Solution.

Q.16. Read the following statements and choose the correct option
Statement 1 : Atria receive blood from all parts of the body which subsequently flows to ventricles.
Statement 2 : Action potential generated at sino-atrial node passes from atria to ventricles.
(a) Action mentioned in Statement 1 is dependent on action mentioned in Statement 2
(b) Action mentioned in Statement 2 is dependent on action mentioned in Statement 1
(c) Action mentioned in Statements 1 and 2 are independent of each other.
(d) Action mentioned in Statements 1 and 2 are synchronous.
Ans. (b)
Solution.
Statement 1: Atria receive blood from all pans of the body which subsequently flows to ventricles.
Statement 2: Action potential generated at sino-atrial node passes from atria to ventricles.
Action mentioned in Statement 2 is dependent on action mentioned in Statement 1.

VERY SHORT ANSWER TYPE QUESTIONS

Q.1. Name the blood component which is viscous and straw coloured fluid.
Ans. Plasma.

Q.2. Complete the missing word in the statement given below:
(a) Plasma without _________ factors is called serum.
(b) ___________ and monocytes are phagocytic cells.
(c) Eosinophils are associated with _____ reactions.
(d) _______ ions play a significant role in clotting.
(e) One can determine the heart beat rate by counting the number of _________ in an ECG
Ans. (a) Plasma without clotting factors is called serum.
(b) Neutrophils and monocytes are phagocytic cells.
(c) Eosinophils are associated with allergic reactions.
(d) Calcium ions play a significant role in clotting.
(e) One can determine the heart beat rate by counting the number of QRS complex in an ECG.

Q.3. Given below is the diagrammatic representation of a standard ECG. Label its different peaks.

Ans:

Q.4. Name the vascular connection that exists between the digestive tract and liver.
Ans. Hepatic portal system

Q.5. Given below are the abnormal conditions related to blood circulation.
Name the disorders.
(a) Acute chest pain due to failure of O₂ supply to heart muscles
(b) Increased systolic pressure
Ans. (a) Acute chest pain due to failure of 0₂ supply to heart muscles—Angina
(b) Increased systolic pressure—Hypertension/high blood pressure

Q.6. Which coronary artery diseases is caused due to narrowing of the lumen of arteries?
Ans. Atherosclerosis

Q.7. Define the following terms and give their location?
(a) Purkinje fibre
(b) Bundle of His
Ans. 
(a) Purkinje fibre—Right and left bundles give rise to minute fibres throughout the ventricular musculature of the respective sides and are called purkinje fibres.
(b) Bundle of His—Purkinje fibres along with right and left bundles are known as bundle of His and present in ventricles.

Q.8. State the functions of the following in blood
(a) Fibrinogen
(b) Globulin
(c) Neutrophils
(d) Lymphocytes
Ans. (a) Fibrinogen—Fibrinogens are needed for clotting or coagulation of blood.
(b) Globulin—Globulins primarily are involved in immunity, i.e., defense mechanisms of the body.
(c) Neutrophils—Phagocytosis
(d) Lymphocytes—Immunity

Q.9. What physiological circumstances lead to erythroblastosis foetalis?
Ans. A special case of Rh incompatibility (mismatching) has been observed between the Rh-negative blood of a pregnant mother with Rh-positive blood of the foetus.

Q.10. Explain the consequences of a situation in which blood does not coagulate.
Ans. This situation leads to excessive loss of blood from body due to injury which can be fatal.

Q.11. What is the significance of time gap in the passage of action potential from sino-atrial node to the ventricle?
Ans. This time gap is significant for ventricular systole.

Q.12. How will you interpret an electrocardiogram (ECG) in which time taken in QRS complex is higher.
Ans. Period of ventricular systole increases