A Level Biology Practice Exam

What is the primary function of ventricles in the heart?

1. To receive blood from the veins and pump it into the lungs

2. To create pressure to pump the blood out of the heart and into the arteries

3. To act as a barrier preventing the backflow of blood

4. To facilitate the exchange of gases in the blood

The correct answer is: To create pressure to pump the blood out of the heart and into the arteries

The primary function of the ventricles in the heart is to create pressure that pumps blood out of the heart and into the arteries. The heart has two ventricles: the right ventricle and the left ventricle. The right ventricle pumps deoxygenated blood into the lungs via the pulmonary arteries for oxygenation, while the left ventricle pumps oxygenated blood into the aorta and out to the rest of the body. This pumping action is critical for maintaining circulation and ensuring that all body tissues receive adequate blood supply and nutrients. Ventricles must generate sufficient pressure to overcome the resistance in the arteries; hence they have thicker muscular walls compared to the atria, which only receive blood. This structural adaptation allows the ventricles to effectively fulfill their role in the circulatory system. The efficiency of this pumping mechanism is essential for overall cardiovascular health. Other answer choices, while relevant to various heart functions, do not accurately capture the primary role of the ventricles. The role of receiving blood from veins is associated with the atria, not the ventricles. The prevention of backflow is managed by valves within the heart rather than the ventricles themselves. Gas exchange occurs in the capillaries and lungs, not directly involving the ventric