Body Fluids and Circulation Test - 1

Platelets are only found in blood.

Serum does not contain clotting factors whereas plasma is composed of serum plus clotting factors.

Albumins help in osmotic balance. Thus, this is matched incorrectly.

Antigen A from donor reacts with anti-A antibody in the recipient. Type B blood contains anti-A antibody that reacts with antigen A from donor.

Both c and d are false because mother-foetus Rh incompatibility is due to Rh^- mother and Rh⁺ foetus. Mixing of Rh⁺ and Rh^- blood occurs during delivery and not during gestation period of first pregnancy. During gestation period, Rh antigens of the foetus do not get exposed to the Rh^- blood of the mother in the first pregnancy as the two bloods are well separated by the placenta.

Thrombokinase, in the presence of Ca²⁺ ions, converts inactive plasma protein called prothrombin into active thrombin. Thus, Ca plays a crucial role in initiation of clotting.

Thrombokinase enzyme converts inactive prothrombin to thrombin enzyme.

In amphibians and reptiles, the left atrium receives oxygenated blood from the gills/lungs/skin and the right atrium gets the deoxygenated blood from other body parts. They get mixed up in the single ventricle, which pumps out mixed blood to the body.

The lubb sound of the cardiac cycle occurs because of the closure of tricuspid and bicuspid valves. They close to prevent back flow of blood from ventricles to auricles.

Rohu is a fresh water fish with two chambered heart. Fish has only two chambers in its heart, one auricle and one ventricle. Since both the auricle and the ventricle remain undivided, only deoxygenated blood passes through it. The deoxygenated blood enters the gills for oxygenation from the ventricle.