Intrinsic factor and hydrochloric acid are produced by:

DSSSB 6 September 2024

Applied Physiology

Easy

Appeared in: DSSSB 6 September 2024

Explanation

Parietal cells, also called oxyntic cells, are located in the gastric glands of the stomach.
These cells are uniquely responsible for secreting two key substances: hydrochloric acid (HCl) and intrinsic factor.
HCl creates the acidic environment of the stomach necessary for digestion and pathogen defense.
Intrinsic factor is a glycoprotein crucial for the absorption of vitamin B₁₂ in the ileum.

Option A: Chief cells are responsible for secreting pepsinogen, the inactive precursor to the protein-digesting enzyme pepsin, not hydrochloric acid or intrinsic factor.
Option B: Zymogen cell is another name for a chief cell. Its primary function is to secrete zymogens (inactive enzyme precursors) like pepsinogen.
Option C: Mucosal neck cells secrete mucus, which forms a protective barrier over the stomach lining to shield it from the harsh acidic environment.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Physiology of Gastric Secretions as background academic context rather than a clinical decision trigger.
A deficiency in intrinsic factor, often due to autoimmune destruction of parietal cells, leads to pernicious anemia, a type of vitamin B₁₂ deficiency. Nurses must be aware of this link when caring for patients with this condition.
Excessive production of hydrochloric acid by parietal cells can contribute to conditions like gastroesophageal reflux disease (GERD) and peptic ulcer disease. Many acid-controlling drugs, such as proton pump inhibitors (e.g., omeprazole), work by directly targeting the proton pumps in parietal cells to reduce acid secretion.
What if? If a patient undergoes a total gastrectomy (removal of the stomach), they will no longer have parietal cells. This means they will produce no intrinsic factor and will require lifelong vitamin B₁₂ injections to prevent pernicious anemia.

How to Approach the Question

First, identify the key substances mentioned in the question: 'Intrinsic factor' and 'hydrochloric acid'.
This is a factual recall question from anatomy and physiology. The task is to remember the specific functions of different cells in the stomach.
Systematically review the options. Think about the primary product of each cell type listed.
Recall that Chief cells produce enzymes (pepsinogen).
Recall that Mucous cells produce mucus for protection.
Recall or deduce that Parietal cells are responsible for the other major secretions: acid (HCl) and intrinsic factor. The name 'parietal' (meaning 'forming the outer wall') might help remember their location in the glands.

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