Q20
1 markMCQSection A

Assertion (A): When ciliary muscles contract, eye lens becomes thin.

Reason (R): Ciliary muscles control the power of the eye lens.

The Human Eye and the Colourful World
The Human Eye

Options

(a)Both, Assertion (A) and Reason (R) are true, and Reason (R) is the correct explanation of Assertion (A).
(b)Both, Assertion (A) and Reason (R) are true, and Reason (R) is not the correct explanation of Assertion (A).
(c)Assertion (A) is true, but Reason (R) is false.
(d)Assertion (A) is false, but Reason (R) is true.
Official Answer

Assertion (A) is false, but Reason (R) is true.

ciliary muscleseye lenspower of the eye lens

Marking Scheme

  • 11 mark

Hint

Think about the role of ciliary muscles in controlling the shape of the eye lens.

Quick Oral Answer

Assertion (A) is false, but Reason (R) is true.

Analysis & Explanation

The ciliary muscles play a crucial role in controlling the shape of the eye lens, which affects the power of the eye lens. However, when the ciliary muscles contract, the eye lens becomes thicker, not thinner.

Common Mistakes

  1. 1Confusing the effect of ciliary muscle contraction on the eye lens.

Interesting Facts

The ciliary muscles are responsible for changing the shape of the eye lens to focus on objects at different distances.

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Frequently Asked Questions

How many marks does this question carry in CBSE Class 10 Science 2025?

This question carries 1 mark in the CBSE Class 10 Science 2025 examination.

Which chapter does this question come from in Science?

This question is from the chapter "The Human Eye and the Colourful World" in the CBSE Class 10 Science syllabus.

What topic does this question cover in Science?

This question covers the topic "The Human Eye" from CBSE Class 10 Science.

What type of question is this in the CBSE Class 10 Science 2025 paper?

This is a MCQ question from Section A in the CBSE Class 10 Science 2025 paper.