Test: Circulatory System In Humans - Class 10 MCQ

The right ventricle (RV) pumps oxygen-poor blood through the pulmonary valve (PV) into the main pulmonary artery (MPA).

From there, the blood flows through the right and left pulmonary arteries into the lungs.

 They may die but do not necessarily bleed to death because there are drugs to help treat this condition called haemophilia. Haemophilia is inherited, or passed on to children by their mothers.  People born with this problem are called haemophiliacs.

It belongs to class Reptilia. All reptiles have three-chambered heart which is divided into two auricles and an incompletely divided ventricle. Only crocodiles have four-chambered heart.

A force is generated with each heartbeat as blood is pumped from the heart into the blood vessels. The size and elasticity of the artery walls also affect blood pressure. Each time the heart beats, pressure is created inside the arteries. That's why option ( c) is the correct answer.

Two chambered heart is present in organisms like fishes. Only one atria and one ventricle is present which are not separated and hence mixing of oxygenated and deoxygenated blood blood occurs.