Science (086) — AI-generated practice question

The stomach secretes hydrochloric acid (HCl) to create an acidic medium for the enzyme pepsin to digest proteins. This acid is highly corrosive and would damage the stomach's own inner lining.

Mucus secreted by the gastric glands protects the inner lining of the stomach from the action of this acid under normal conditions.

If insufficient mucus is produced, the acid will attack and erode the stomach lining, causing pain, inflammation, and ulcers — a condition commonly associated with acidity or hyperacidity.

Source: Chapter 5, Section 5.2.4 — Nutrition in Human Beings

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• Examiners expect you to link HCl → need for protection → role of mucus → consequence of insufficient mucus in a logical chain.
• The textbook directly states: "The mucus protects the inner lining of the stomach from the action of the acid under normal conditions," and links its absence to acidity — mention this explicitly.
• The word "ulcer" is a reasonable inference and acceptable; the textbook hints at it through the "acidity" reference.
• For 3 marks, cover: (1) why acid is needed, (2) what mucus does, (3) consequence without it.