Adult human RBCs are enucleate. Which of the following statement(s) is/are most appropriate explanation for this feature?
(I) They do not need to reproduce.
(II) They are somatic cells.
(III) They do not metabolise.
(IV) All their internal space is available for oxygen transport.

1. Only (IV)
2. Only (I)
3. (I), (III) and (IV)
4. (II) and (III)

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

In mammals, which blood vessel would normally carry largest amount of urea?
1. Dorsal aorta
2. Hepatic vein
3. Hepatic portal vein
4. Renal vein

Blood pressure in the pulmonary artery is
1. more than that in the carotid
2. more than that in the pulmonary vein
3. less than that in the venae cavae
4. same as that in the aorta

Doctors use a stethoscope to hear the sounds produced during each cardiac cycle. The second sound is heard when

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?

Consider the following statements:
I. Heparin can be used as anticoagulant both in-vivo and in vitro.
II. Plasmin prevents thrombus formation.
III. Lack of factor IX causes hemophilia B.
Which of the above statements are true?
1. I and II only           2. I and III only
3. II and III only         4. I, II, and III

Consider the following statements:

Which of the above statements are true?