Read the statements given below and choose the correct option: Assertion (A):…
2023
Read the statements given below and choose the correct option:
Assertion (A): Stomach produces hydrochloric acid that helps in breakdown of food.
Reason (R): Digestive juices need an acidic medium to act.
- A.
(A) is true, but (R) is false.
- B.
Both (A) and (R) are true, but (R) is not the correct explanation of (A).
- C.
(A) is false, but (R) is true.
- D.
Both (A) and (R) are true and (R) is the correct explanation of (A).
Show answer & explanation
Correct answer: D
CONCEPT: In an assertion-reason item, first judge whether the Assertion (A) and the Reason (R) are independently true, then judge whether (R) causally explains (A). For human digestion, the stomach's gastric glands secrete hydrochloric acid (HCl) to create a strongly acidic environment (pH about 1.5 to 3.5). This acidity is essential because digestive enzymes are pH-specific: pepsinogen is converted into active pepsin only in an acidic medium, and pepsin itself works best at low pH to break down proteins.
APPLICATION: Here, Assertion (A) - the stomach produces HCl that helps break down food - is scientifically correct. Reason (R) - digestive juices need an acidic medium to act - is also correct in the context Assertion (A) sets up, and it is exactly why (A) happens: without the acidic medium HCl provides, the stomach's digestive enzymes could not become active or function. So (R) is the correct explanation of (A).
CROSS-CHECK:
The claim that (R) is false fails because the digestive enzymes in gastric juice genuinely do require an acidic medium to act - a true physiological fact, though (as the note below explains) it does not extend to every digestive secretion in the body.
The claim that (R) does not explain (A) fails because the acidic medium (R) describes is precisely the mechanism that lets the stomach's enzymes activate and act on food.
The claim that (A) is false fails because the stomach's gastric glands do secrete hydrochloric acid that aids in breaking down food.
Note: Reason (R)'s "digestive juices" refers here to the stomach's own gastric juice, in line with Assertion (A)'s focus on the stomach; taken in that scope, the statement is true. Other digestive secretions elsewhere in the gut, such as pancreatic juice and intestinal juice, work in an alkaline medium, but that is outside what Assertion (A) describes.
Hence, both statements are true and (R) correctly explains (A), as confirmed by the official CTET answer key for this item.