Question:medium
The main site of water absorption is?
The main site of water absorption is?
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Compare absolute volumes: the proximal small bowel reclaims the most, not the colon.
Updated On: Jun 24, 2026
- Jejunum
- Colon
- Ileum
- Stomach
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The Correct Option is A
Solution and Explanation
Water movement across the gut follows sodium and solute transport, so the segment that handles the greatest osmotic and nutrient load also reabsorbs the most water. The daily fluid budget makes the answer quantitative rather than a matter of opinion.
On a typical day the gut sees close to 9000 mL of water: about 2000 mL swallowed in food and drink, plus roughly 7000 mL secreted by the salivary glands, stomach, pancreas, liver and intestine. Almost all of this must be recovered to avoid dehydration.
Breaking down where it goes: the jejunum reclaims the largest share at around 5500 mL, the ileum recovers about 2000 mL, and the colon mops up around 1300 mL. Only about 200 mL leaves the body in faeces.
Even though the colon is famous for concentrating stool, the absolute volume it absorbs is small compared with the proximal small bowel. The jejunum, with its high surface area and vigorous sodium-coupled transport, absorbs by far the most water of the listed sites.
\[\boxed{\text{Jejunum}}\]
On a typical day the gut sees close to 9000 mL of water: about 2000 mL swallowed in food and drink, plus roughly 7000 mL secreted by the salivary glands, stomach, pancreas, liver and intestine. Almost all of this must be recovered to avoid dehydration.
Breaking down where it goes: the jejunum reclaims the largest share at around 5500 mL, the ileum recovers about 2000 mL, and the colon mops up around 1300 mL. Only about 200 mL leaves the body in faeces.
Even though the colon is famous for concentrating stool, the absolute volume it absorbs is small compared with the proximal small bowel. The jejunum, with its high surface area and vigorous sodium-coupled transport, absorbs by far the most water of the listed sites.
\[\boxed{\text{Jejunum}}\]
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