Which component of the human circulatory system prevents the backflow of deoxygenated blood as it returns to the heart?
Answer and explanation
Correct answer: A. One-way venous valves
- Step 1: Blood pressure is very low in the venous system, especially below heart level. Step 2. Veins feature one-way valves that prevent retrograde flow against gravity back down toward extremities. Answer: One-way venous valves. Why not the others: Arteries maintain high pressure via elastic walls; capillaries lack valves.
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