Structures Of The Eye

Question 1

Optic nerve

Answer 1

It is the second of several pairs of cranial nerves. The job of the optic nerve is to transfer visual information from the retina to the vision centers of the brain via electrical impulses.

Question 2

Iris

Answer 2

The iris is a thin, circular structure in the eye, responsible for controlling the diameter and size of the pupil and thus the amount of light reaching the retina.

Question 3

Retina

Answer 3

The retina is a thin layer of tissue that lines the back of the eye on the inside. It is located near the optic nerve. The purpose of the retina is to receive light that the lens has focused, convert the light into neural signals, and send these signals on to the brain for visual recognition.

Question 4

Lens

Answer 4

The lens, by changing shape, functions to change the focal distance of the eye so that it can focus on objects at various distances, thus allowing a sharp real image of the object of interest to be formed on the retina.

Question 5

Pupil

Answer 5

The primary function of the human pupil is to regulate the amount of light that enters the eye. When the pupil is smaller, less light enters the eye in bright environments. The pupil gets larger as light levels decrease to let more light into the eye.

Question 6

Vitreous humour

Answer 6

Additionally, the vitreous humor fills much of the eye, allowing light to pass through the lens to the retina and helping the eye to keep its round shape.

Question 7

Aqueous humour

Answer 7

Aqueous is a thin, watery fluid located in the anterior and posterior chambers of the eye. The anterior chamber lies between the iris (colored part of the eye) and the inner surface of the cornea (the front of the eye). The posterior chamber is located behind the iris and in front of the lens.

Question 8

Cornea

Answer 8

The cornea shares this protective task with the eyelids, the eye socket, tears, and the sclera, or white part of the eye. The cornea acts as the eye’s outermost lens. It functions like a window that controls and focuses the entry of light into the eye.

Question 9

Blind Spot

Answer 9

Blind spot, small portion of the visual field of each eye that corresponds to the position of the optic disk (also known as the optic nerve head) within the retina. There are no photoreceptors (i.e., rods or cones) in the optic disk, and, therefore, there is no image detection in this area.

Question 10

first version of the eye

Answer 10

A limpet contains light-sensitive cells connected to a nerve which is the most basic version of eyes and are just clusters of photoreceptor cells. Pigment cells are sensitive to light.

Question 11

second version of the eye

Answer 11

An Eyecup is a slightly more refined version of the eye. They have their photoreceptors cells lining cup-shaped indentations on their heads.These cups have no lenses but allow the animal to distinguishh light from dark.

Question 12

third version of the eye

Answer 12

Simple pinhole camera-type eyes have a fluid field cavity and has a layer of light sensitive cells which is mainly found at the bottom of the eye

Question 13

fourth version of the eye

Answer 13

Eyes with a primitive lens has similar attributes to the simple pinhole camera-type eye, but have a larger retina and eye cup and contains a lens, with a transparent protective tissue (cornea) covering it.

Question 14

fifth version of the eye

Answer 14

The complex camera type eye is another progression and similar to the eye with a primitive lens, but its retina and eyecup are larger and its eyecup goes all the way up to the cornea which helps filter light through the eye and with the help of the lens displays it on the retina.

Question 15

what is the pax 6 gene

Answer 15

Pax 6 gene was proved to be the universal control gene for the eye, through an experiment thought of by Gehring.

Question 16

traditional idea of the eye forming

Answer 16

The traditional idea is that the eyes evolved separately into separate anima phyla. Because each eye looks unique based on each species, it was traditionally assumed that they evolved quite differently. Because of this each species would have a unique type of contruction, for example the human eye was created by our brains forming an invagination, and a bulb inside of us was moving outwards towards the skin.

Question 17

new idea of the eye forming

Answer 17

The new idea is that we all have the same genetic basis in all animal phyla. Which leads us to the modern view that the eye was invented only once. Then different phyla used the basic eye and make various types of it.

Question 18

Why was the detection of life so important in the sea

Answer 18

Having vision in the sea would be huge advantage as it would give the owner the ability to detect sunlight. Sunlight is characterized by a heavy UV wave which can cause extreme harm to a single cell organism if that are exposed to too much. If the single cell organism had vision and ability to detect light, they would swim downwards to escape the sunlight during the day, and swim back up during the night. This would give them a better chance of survival and ultimately cause them to adapt this trait.