Question 1

Which of the following cells do not exhibit phagocytotic activity?

Accepted Answer

(c) Basophil are least common of granulocyte, only composed of 0.01% to 0.3% of the circulating white blood cells. These are involved in specific kinds of inflammatory reactions, particularly those which cause allergic reactions and do not exhibit phagocytotic activityWhereas, monocytes migrate from blood stream to tissue and differentiate into resident macrophage, e.g., kupffer cells in liver and neutrophils target bacteria and fungi. Macrophages are also phagocytotic in nature.

Question 2

Which among the followings is correct during each cardiac cycle?

Accepted Answer

Cardiac Cycle consists of one heart beat or one cycle of contraction and relaxation of the cardiac muscle. The contraction phase is called the systole while the relaxation phase is called the diastole.The purpose of cardiac cycle is to effectively pump the blood. The right ventricle pumps the volume of deoxygenated blood to the lungs through pulmonary artery. After the oxygenation of blood the volume of blood carried through pulmonary vein is pumped through left ventricle into the aorta and transferred to the entire body. This pumping of blood, is about the same and any mismatch in volumes ejected by the ventricles (i.e., right ventricle pump more blood than left or vice versa) can result in the heart failure. Thus, all the other option are wrong.

Question 3

Cardiac activity could be moderated by the autonomous neural system.Tick the correct answer.

Accepted Answer

Neural signals through the sympathetic nerves can increase the rate of the heart beat, the strength of ventricular contraction and thereby stimulating the cardiac output. Hence, sympathetic system is involved in stimulating heart rate and stroke volume. Therefore, other options are wrong.

Question 4

Mark the pair of substances among the following which is essential for coagulation of blood.

Accepted Answer

Certain factors released by the tissues at the site of injury can initiate coagulation process.Calcium ions and platelet factor act in the first step of coagulation which is as follows:(i) At the site of an injury, the blood platelets disintegrate and release a phospholipid, called platelet factor 3 (platelet thromboplastin).(ii) Injured tissues also release a lipoprotein factor called thromboplastin.(iii) These two factor combine with calcium (Ca2+) ions and certain proteins of the blood plasma to form an enzyme called pro-thrombinase.(iv) Prothrombiminase catalyzes prothrombin into active protein called thrombin.(v) Thrombin further converts inative fibrinogens into fibrin in the blood plasma.(vi) Then the long fibres of fibrin form a dense network upon wound and trap blood corpuscles RBCs, WBCs and platelets) to form a clot.And the other options are wrong.

Question 5

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.

Accepted Answer

A normal ECG represents P-wave atrial depolarisation QRS complex-ventricular depolarisation T-wave ventricular repolarisation. Therefore, atrial repolarisation is not represented is not represented in an electrocardiogram (ECG).

Question 6

Which of the following type of cells lack nucleus in hormones?

Accepted Answer

RBCs (Red Blood Corpuscles) in humans lack nucleus. Absence of nucleus in the cell reduces the O2​ consumption by the cell in various cellular activities. Therefore, the cell is able to transport maximum amount of O2​ to other cells of the body.Other cells like neutrophils, eosinophils and monocytes possess nucleus of varied shape and size as shown below.

Question 7

Which one of the following blood cells is involved in antibody production.

Accepted Answer

B-lymphocytes: Their principal function is to make antibodies against soluble antigens that are important in regulating humoral immunity. On the other hand RBCs transport oxygen, T-lymphocytes play central role in cell mediated immunity and neutrophils acts as phagocytes.

Question 8

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

Accepted Answer

(c) SA Node: It is situated in the walls of the right auricle near the opening of the superior vena cava. In myogenic heart the contraction is initiated by SA node. AV Node: The wave of contraction reaches AV node which is stimulated to emit an impulse of contraction spreading to the ventricular muscle via the atrio ventricular bundle and then to the Purkinje fibres stimulating heart beat.

Question 9

Agranulocytes responsible for immune response of the body are

Accepted Answer

Lymphocytes are white blood cells responsible for immune response of the body. These cells recognise and react with antigens.Basophils contain anticoagulant heparin which prevents blood form a clotting and also contain vasodilator histamine which promotes blood flow into the tissues. Eosinophils are white blood cells which defend the body against parasitic infections.

Question 10

The second heart sound (dubb) is associated with the closure of

Accepted Answer

During each cardiac cycle two prominent sounds are produced which can be easily heard through a stethoscope. Semilunar value- The second sound of the heart is high pitched ‘DUB’ It is caused by vibrations associated with closure of aortic and pulmonary valves. It lasts for an about 0.12 seconds with the frequency of 50 Hz, while tricuspid value, bicuspid value and both the value together are associates with first heart (i e. ., lubb).

Question 11

Which of the following correctly explains a phase/event in cardiac cycle in a standard electrocardiogram?

Accepted Answer

(b) QRS Complex QRS wave (complex) begins after a fraction of second after the P wave. It begins as a small downward deflection (Q) and continuous as a large upright (R) and triangular wave, ending as downward wave (S) at its base. This represents ventricular depolarisation (ventricular contraction). Thus, the other options are wrong.

Question 12

One of the common symptoms observed in people infected with dengue fever is

Accepted Answer

The low platelet count leads to life threatening condition and is one of the most common symptoms observed in people infected with dengue fever whereas, other options are not the symptoms of dengue fever.

Question 13

Which of the following statements is incorrect?

Accepted Answer

ABO blood grouping in human is based on the presence or absence of two surface antigens on the RBCs namely A and B. Similarly, the plasma of different individuals contain two natural antibodies. This distribution of antigens and antibodies in the four groups of blood A, B, AB and O are as followsThus, blood group in universal donor 4 blood group AB in universal recipient and the other options are correct.

Question 14

What would be the cardiac output of a person having 72 heart beats per minute and a stroke volume of 50 mL?

Accepted Answer

(d) Cardiac Output(i) The volume of blood pumped by each ventricle per minute is called the cardiac output. It is 500 mL or 5 litres in a healthy individual.(ii) It is determined by multiplying the heart rate with the volume of blood ejected by each ventricle during each beat, which is called as stroke volume.Cardiac output = Heart rate × Stroke volume =72 beats /min×0.08 litre / beat =5.5 litre /min(iii) Cardiac index is the minute volume per sq. m. of body surface area. Its normal value is 3.3 lit /min/sq.m.

Question 15

Match the following columns.

Accepted Answer

The correct matching is as listed below

Question 16

Read the following statements and choose the correct option. Statement I: Atria receive blood from all parts of the body which subsequently flows to ventricles. Statement II: Action potential generated at sino-atrial node passes from atria to ventricles.

Accepted Answer

The superior vena cava pours venous blood into right atria and left atria receive blood from lungs. This then flows into ventricles. The contraction of muscles of atria arise from SA nodes and passes to AV node and then to the Purkinje fibres.Therefore, action mentioned in statement I and II are synchronous, while the other options are wrong.

Question 17

Name the blood component which is viscous and straw coloured fluid.

Accepted Answer

Blood is a special connective tissue consisting of a fluid matrix, plasma and cells. Plasma is a straw coloured, viscous fluid constituting of nearly 55 % of the blood, 90-92% of plasma is water and proteins contributes approx 6-8% . The plasma proteins contains fibrinogen, globulins and albumins.

Question 18

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 heartbeat rate by counting the number of ......... in an ECG.

Accepted Answer

(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.

Question 19

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

Accepted Answer

The representation of a standard ECG diagram

Question 20

Name the vascular connection that exists between the digestive tract and liver.

Accepted Answer

The unique vascular connection that, exists between the digestive tract and liver is called hepatic portal system.

Chapter 18 : Body Fluids and Circulation