Chapter 33, Problem 7STP

Summary Introduction

Introduction:

The human eye is one of the vital organs of the human body. The eye is slightly asymmetrical in structure and includes different parts that help us to see things. The iris is the colored part, the cornea is the clear dome over the iris, the pupil is the circular opening in the iris, the sclera is the white of the eye, and conjunctiva is the thin layer of tissue that covers the whole eye except the cornea, consisting the outer part of an eye. The inner part comprises of light-sensing cells that is the retina, it helps in the conversion of light to electric impulse. The impulse through the optic nerve is transmitted to the brain.

Answer to Problem 7STP

Correct answer:

The correct answer is option (C) 3.

Explanation of Solution

Explanation/justification for the correct answer:

Option (C). The label 3 represents the retina. The retina helps in the conversion of light to electric impulse. The impulse through the optic nerve is transmitted to the brain. Retina is also involved in the detection of color, therefore people with damaged retina are not able to see color. So, the correct answer is option (C).

Explanation for incorrect answer:

Option (A) The label 1 represents the iris. Iris is the colored part of the eye that is involved in the maintenance of what amount of light to enter inside the eye when the light is bright the pupil gets close to avoid an excess of light. So, this is an incorrect option.

Option (B) The label 2 represents the lens. Lens and cornea helps to focus the rays of light to the retina where it gets converted to electric impulse. So, this is an incorrect answer.

Option (D) The label 4 represents the optic nerve. It is the part of the nervous system found in the back of the eye. The light is converted to electric impulse thus carried by the optic nerve that passes the stimuli to the brain. So, this is an incorrect answer.