Gastrointestinal: ileocaecal valve: practice question

A Physiology question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

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Physiology · Gastrointestinal: ileocaecal valve

Sample item

A patient who has had the ileocaecal valve resected develops diarrhoea with bacterial overgrowth of the distal small bowel. Which normal function of the valve has been lost?

ASecretion of intrinsic factor for vitamin B12 absorptionBBarrier against reflux of colonic contents and control of ileal emptyingCAbsorption of bile salts at the valveDMixing of chyme by segmentation movements

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

B. Barrier against reflux of colonic contents and control of ileal emptying

The ileocaecal sphincter normally prevents reflux of colonic contents and bacteria into the ileum, and it regulates the rate at which ileal chyme enters the caecum. When it is lost, colonic bacteria colonise the terminal ileum, and rapid ileal emptying overloads the colon.

Option by option

A. Secretion of intrinsic factor for vitamin B12 absorption
Intrinsic factor is made by gastric parietal cells.
B. Barrier against reflux of colonic contents and control of ileal emptying (correct)
Correct. The valve is a barrier and a regulator of ileal emptying.
C. Absorption of bile salts at the valve
Bile salts are absorbed by the terminal ileal mucosa, not at the valve.
D. Mixing of chyme by segmentation movements
Segmentation is a motility pattern of the small bowel wall and is not a function of the valve.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

Questions about this Physiology question

What is the answer to this Physiology question?

The best answer is B, Barrier against reflux of colonic contents and control of ileal emptying. The ileocaecal sphincter normally prevents reflux of colonic contents and bacteria into the ileum, and it regulates the rate at which ileal chyme enters the caecum.

Why is "Secretion of intrinsic factor for vitamin B12 absorption" not the answer?

Intrinsic factor is made by gastric parietal cells.

Why is "Absorption of bile salts at the valve" not the answer?

Bile salts are absorbed by the terminal ileal mucosa, not at the valve.

Why is "Mixing of chyme by segmentation movements" not the answer?

Segmentation is a motility pattern of the small bowel wall and is not a function of the valve.

What concept does this question test?

It tests Gastrointestinal: ileocaecal valve in Physiology. When it is lost, colonic bacteria colonise the terminal ileum, and rapid ileal emptying overloads the colon.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Gastrointestinal: ileocaecal valve?

For each system, sketch the key graph (pressure–volume loop, oxygen dissociation curve, nephron handling) and explain it aloud. Then use the flashcards and the other Physiology questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.