A Level Biology Practice Exam

What does systemic circulation involve in the cardiovascular system?

1. Transporting deoxygenated blood from the lungs

2. Carrying oxygenated blood to the heart

3. Delivering oxygen to body tissues directly

4. Circulation of oxygenated blood from the heart to the body

The correct answer is: Circulation of oxygenated blood from the heart to the body

Systemic circulation is a key component of the cardiovascular system that involves the circulation of oxygenated blood from the heart to all body tissues. This process starts when oxygen-rich blood is pumped from the left ventricle of the heart through the aorta, the largest artery in the body. From there, the blood travels through progressively smaller arteries and arterioles until it reaches the capillary networks throughout various tissues and organs. At the capillaries, oxygen and nutrients are delivered to the cells, while carbon dioxide and other metabolic wastes are collected for transport back to the heart. Once the exchange has occurred, deoxygenated blood returns to the heart through venules and veins, completing the cycle. This function is essential for providing the body's cells with the necessary oxygen and nutrients required for cellular respiration and overall metabolism. Understanding systemic circulation is vital for comprehending how the body maintains homeostasis and supports life through the efficient transport of substances. The other options do not correctly describe the primary role of systemic circulation, focusing instead on processes like pulmonary circulation or specific functions within the overall circulatory system that are not exclusive to systemic circulation.