Increase in splanchnic blood flow during eating can ______ absorption because more blood flow maintains a strong concentration gradient that increases net movement.

Increase in splanchnic blood flow during eating can ______ absorption because more blood flow maintains a strong concentration gradient that increases net movement.

• A. Decrease absorption
• B. No effect
• C. Increase absorption
• D. Increase absorption due to maintained gradient

Answer: (D)

When you eat, splanchnic blood flow to the gut increases. Absorption across the intestinal wall depends on a concentration gradient between the lumen (where nutrients are present at high levels after a meal) and the blood. Increased blood flow helps by rapidly removing absorbed nutrients from the mucosal area, keeping the blood-side concentration low and the luminal concentration relatively high. This maintains a strong gradient, so nutrients move into the blood more readily. So absorption increases because the heightened perfusion sustains the gradient that drives net transfer.

When you eat, splanchnic blood flow to the gut increases. Absorption across the intestinal wall depends on a concentration gradient between the lumen (where nutrients are present at high levels after a meal) and the blood. Increased blood flow helps by rapidly removing absorbed nutrients from the mucosal area, keeping the blood-side concentration low and the luminal concentration relatively high. This maintains a strong gradient, so nutrients move into the blood more readily. So absorption increases because the heightened perfusion sustains the gradient that drives net transfer.