ASVAB (Armed Services Vocational Aptitude Battery)Paragraph Comprehension (PC)Medium
Read the following passage: "The human circulatory system is a vast network of organs and vessels responsible for the flow of blood, nutrients, hormones, oxygen, and other gases to and from cells. It consists of three main components: the heart, blood vessels (arteries, veins, and capillaries), and blood. The heart acts as a powerful pump, propelling blood throughout the body. Arteries carry oxygenated blood away from the heart, while veins return deoxygenated blood to the heart. Capillaries, the tiniest blood vessels, facilitate the exchange of oxygen, nutrients, and waste products between the blood and body tissues. The entire system is crucial for maintaining homeostasis and ensuring the proper functioning of all bodily systems. A malfunction in any component can have widespread health implications." What is the specific role of capillaries in the circulatory system?
- APumping blood to the lungs for oxygenation
- BReturning deoxygenated blood to the heart
- CCarrying oxygenated blood away from the heart
- DFacilitating exchange between blood and body tissues
Show answer & explanationAnswer & explanation
Correct answer: D. Facilitating exchange between blood and body tissues
The passage explicitly states, 'Capillaries, the tiniest blood vessels, facilitate the exchange of oxygen, nutrients, and waste products between the blood and body tissues.'
Why the other options are wrong
- A. This is a function of the heart and pulmonary arteries, not capillaries.
- B. This is the role of veins.
- C. This is the role of arteries.
Capillary Function
Capillaries are the smallest blood vessels, responsible for the vital exchange of gases, nutrients, and waste products between the blood and body cells.
- Connect arterioles and venules.
- Have very thin walls (one cell thick) for efficient diffusion.
- Form extensive networks within tissues.
Memory trick: Capillaries Carry out Crucial Cellular Commerce.