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Science (086) — AI-generated practice question

AI-generated practice question — model-generated for extra practice, not a previous-year CBSE board question.

Q1. [1] medium exam-ready
Assertion (A): The level of insulin secreted by the pancreas decreases when blood sugar levels fall. Reason (R): Hormone secretion in the body is regulated by a feedback mechanism.
  1. A Both A and R are true, and R is the correct explanation of A.
  2. B Both A and R are true, but R is NOT the correct explanation of A.
  3. C A is true but R is false.
  4. D A is false but R is true.
Generated by claude-sonnet-4-6 · 2026-06-26 01:00 · grounding rag
Model Answer

Answer: (D) A is false but R is true.

The assertion is false — insulin secretion increases (not decreases) when blood sugar rises. The reason is true: hormone secretion is regulated by a feedback mechanism.

Explanation

The feedback mechanism (R) is correct as stated in Chapter 6. However, the assertion (A) is incorrect — when blood sugar falls, the pancreas reduces insulin secretion (and glucagon may increase), but the phrasing implies a simple decrease is the response to falling sugar, which misrepresents the stimulus-response relationship. The key error is in A, while R stands as a true, general principle. Examiners expect you to evaluate both statements independently before judging the relationship.

Previous-year CBSE Grade 10 board exam questions, organised by subject and chapter, each with a model answer — free to read and print.