Question

Explain the working and functions and different parts of human eye.

Worth 25 points, please help ASAP,it's due the day after tomorrow.

Answer 1

Our paired eyes are located in sockets of the skull called orbits
Parts of an eye:
The adult human eye ball is nearly a spherical structure. The wall of the eye ball is composed of three layers. The external layer is composed of a dense connective tissue and is called the sclera. The anterior portion of this layer is called the cornea. The middle layer choroid contains many blood vessels and looks bluish in colour. The choroid layer is thin over the posterior two_thirds of the eye ball, the ciliary body itself continues forward to form a pigmented and opaque structure called the iris which is the visible colored portion of the eye. The eye ball contains a transparent crystalline lens which is held in place by ligaments attached to the ciliary body. In front of the lens, the aperture surrounded by the iris is called the pupil. The diameter of the pupil is regulated by the muscle fibres of iris.
The inner layer is retina and it contains three layers of cells_ from inside to outside_ganglion cells, bipolar cells and photoreceptor cells.

Answer 2

The human eye can be compared to a camera which gathers, focuses, and transmits light through a lens to create an image of the environment. In a camera, the image is created on film; in the eye, the image is created on the retina, a thin layer of light sensitive cells at the back of the eye.