Question

The aperture in the eye through which light enters is the

• A. Pupil
• B. Conjunctiva
• C. Ciliary muscles
• D. Choroid

Answer 1

The correct option is A

Pupil

The correct option is A.

Explanation of correct option:

1. The pupil is an aperture surrounded by the iris in an eye through which light enters the eye.
2. The size of the pupil is controlled by the movement of the muscle fiber of the iris regulating the quantity of light penetrating the eye.
3. When the light intensity increases there is a constriction of the iris and the pupil.

Explanation of incorrect options:

Option B:

1. The conjunctiva of the eye is responsible for the production of mucus and tears in order to protect and lubricate the eye.
2. It helps to keep bacteria out of the eye and aids in immune scrutiny.

Option C:

1. The ciliary muscle is an intrinsic eye muscle that is developed as a ring of smooth muscle in the central layer of the eye, called the uvea (vascular layer).
2. It regulates the flow of aqueous humor and regulates arrangements for viewing objects at different distances.

Option D:

1. The choroid is the middle layer of an eye which is rich in blood vessels and helps in its nourishment.
2. It is a thin layer of tissue between the sclera and the retina that regulates the volume and temperature of an eye by providing nutrients to the outer retina.

Final answer: The aperture in the eye through which light enters is the pupil.