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Read the assertion and reson carefully t...

Read the assertion and reson carefully to mark the correct option out of the options given below:
Assertion : Circular smooth muscles of iris contract when bright light falls on the eye .
Reason : Pupil gets constricted by the contraction of circular smooth muscles of iris .

A

If both the assertion and the reason are true and the reason is a correct explanation of the assertion

B

If both the assertion and reason are true but the reason is not a correct explanation of the assertion

C

If the assertion is true but the reason is false

D

If both the assertion and reason are false

Text Solution

Verified by Experts

The correct Answer is:
B
Iris is made up of smooth muscle fibres are organized in two groups:
* Circular muscle: It acts as a sphincter, when it contracts, the pupil get smaller and the amount of light entering decreases.
* Radial muscles: When these muscles contact the pupil’s diameter increases and the amount of light entering increases.
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