Which of the following plasma protein helps in coagulation of blood ?

1. Fibrin

2. Prothrombin

3. Vitamin K

4. Albumin

Which of the following disorders of circulatory system is not correctly stated?

(1) Hypertension – A sustained blood pressure of 140/90 or above

(2) CAD – The lumen of coronary arteries become narrower due to deposits of calcium, fat, cholesterol and fibrous tissue

(3) Atherosclerosis – Heart muscle is suddenly damaged by inadequate blood supply

(4) Heart failure – Usually called congestive heart failure because congestion of lungs is one of the main symptoms of the disease

In a mm³ of blood, the maximum number and minimum number of cells would be respectively

1. WBCs, RBCs

2. RBCs, WBCs

3. RBCs, Platelets

4. Platelets, WBCs

Which of the following statements is not true for the human heart?

1. Adrenal medullary hormones can increase the cardiac output

2. Neural signal through the sympathetic nerves can initiate the heart beat

3. Increase in BMR due to thyroxine can indirectly increase heart rate

4. Strength of ventricular contraction and cardiac output is increased by catecholamines

Which of the following is least likely to be caused by reduced blood/oxygen supply to heart muscles?

1. Atherosclerosis

2. Myocardial ischaemia

3. Angina pectoris

4. Heart attack

Choose the incorrect match with respect to blood components

1. Leucocytes – 6000 - 8000 mm^–3

2. Globulins – Involved in defence mechanisms

3. O^– blood group – Antibodies A and B absent

4. Thrombokinase – Converts prothrombin into thrombin

Choose the incorrect match
(1) Cardiac arrest – Condition in which heart

                                  stops beating

(2) T-wave –          Represents depolarization

                            of ventricles

(3) SAN –             Generates maximum
                           number of action
                           potentials

(4) P-wave –          Represents contraction of

                          both atria

Atrial systole

1.  Increases the flow of blood into the ventricles by 70 percent

2.  Is due to the generation of the action potential in AVN

3.  Increases the flow of blood into the ventricles by 30 percent

4.  Coincides with ventricular systole

During ECG of a healthy person, P-wave represents

1. Ventricular depolarisation

2. Ventricular repolarisation

3. Joint diastole

4. Atrial depolarisation

Which of the following is known as the natural pacemaker of the heart?

1.  Sino atrial node

2.  Atrioventricular node

3.  Bundle of His

4.  Purkinje fibers