EPFO 2004 PYQ with Answer — 35. Why does bleeding occur through nose in high mountainous regions?

2004 · Q35

35. Why does bleeding occur through nose in high mountainous regions?

General ScienceBiology

AThe pressure of blood in capillaries is greater than the outside pressure
BThe pressure at high altitudes is greater than that on the plains
CThe blood pressure of a person increases at high altitudes
DThe blood pressure fluctuates and finally decreases drastically

Explanation

At high altitudes the outside atmospheric pressure is much lower than at the plains, while the blood pressure inside the nasal capillaries remains comparatively high. This pressure gradient across the thin capillary walls can rupture them, causing nosebleeds. The outside pressure is lower (not greater), and the mechanism is the pressure difference — not a rise in blood pressure itself.