Question Detail

PHY 104 The Human Eye Objective Question
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Question

The human eye adjusts its focal length to focus objects at varying distances on the retina. What mechanism is primarily responsible for changing the focal length of the eye's lens?
Options
A Contraction and relaxation of the iris.
B Changes in the curvature of the cornea.
C Contraction and relaxation of the ciliary muscle, altering lens shape.
Correct Answer
D Movement of the retina forward or backward.
Correct Answer

Option C is the correct answer.

Detailed Explanation

The text states: 'the tension in the ciliary muscle increases and it contracts, causing the lens to bulge and its radius of curvature to change.' This process directly alters the shape, and thus the focal length, of the crystalline lens.

Hint

Think about how the eye 'accommodates' to see objects at different distances.

Question Info

Course: PHY 104
Topic: The Human Eye
Type: Objective
Difficulty: Not specified
Question 609 of 947
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