The right atria of the human heart receive:
1. Oxygenated blood
2. Deoxygenated blood
3. Arterial blood
4. Venous blood

The following is the diagrammatic representation of standard ECG. Identify the correct statement :

In the given section of the human heart which part ensures that atria contact prior to the ventricles ?

1. A

2. B

3. C

4. D

The hepatic portal vein drains blood to liver from 
(1) heart

(2) stomach

(3) kidneys

(4) intestine

Name the blood cells, whose reduction in number can cause clotting disorder, leading to excessive loss of blood from the body.

(1) Erythrocytes                       

(2) Leucocytes

(3) Neutrophils                         

(4) Thrombocytes

Serum differs from blood in 

(1) lacking globulins

(2) lacking albumins

(3) lacking clotting factors

(4) lacking antibodies

Doctors use a stethoscope to hear the sounds produced during each cardiac cycle. The

second sound is heard when

1. AV valves open up

2. Ventricular walls vibrate due to gushing in of blood from atria

3. Semilunar valves close down after the blood flows into vessels from ventricles

4. AV node receives the signal from SA node

Person with blood group AB is considered as universal recipient because he has

1. Both A and B antigens on RBC but no antibodies in the plasma

2. Both A and B antibodies in the plasma

3. No antigen on RBC and antibody in the plasma

4. Both A and B antigens in the plasma but no antibodies.

How do parasympathetic neural signals affect the working of the heart?

1. Reduce both heart rate and cardiac output

2. heart rate is increased without affecting the cardiac output

3. Both heart rate and cardiac output increase

4. Heart rate decreases but cardiac output increases

The diagram given here is the standard ECG of a normal person. the P-wave represents

the

1. contraction of both the atria

2. initiation of the ventricular contraction

3. beginning of the systole

4. end of systole