Eye and Ear and their parts (principles of psychology B.s 4th semester notes)

Principles of psychology B.S zoology 4th semester



Table of Contents

1. Eye Definition

2. Eye parts

3. Ear and its parts

4. Perception

5. Attention

, EYE
Definition: The eye is an organ that detects light and sends signals along the optic nerve to the
brain. In humans, the eye is valuable sense organ that gives us the ability to see. It allows for
light perception and vision, including the ability to differentiate between colors and depth.




Tunic: Anatomically, the wall of the eye ball can be divided into three layers known as tunic.

• Fibrous tunic
• Vascular tunic
• Nervous tunic
Fibrous tunic: The outermost surface of the eyeball. It consists of three tissues;

• The sclera
• The conjunctiva
• The cornea
Sclera: The sclera covers over 80% of the eyeball. Though, fibrous layer which maintain the
shape of the eyeball. It protects the eye. It is often referred to as the white of the eye.
Conjunctiva: The sclera at the front of the eye is itself covered by conjunctiva. A thin
transparent membrane that only covers the sclera but also the lens underside of the eyelids.
Cornea: The tough transparent membrane of the outer layer of the eyeball that covers the iris
and the pupil.
Vascular Tunic: Middle layer of the eye ball. It consists of three tissues;