Vision

Question 1

What is the visible part of the electromagnetic spectrum?

Answer 1

400nm - 700nm

Question 2

What is the sclera?

Answer 2

Tough outer coat that protects the entire eyeball which is a tough fibrous tissue that extends from the cornea to the optic nerve at the back of the eye.

Question 3

What is the choroid?

Answer 3

Vascular layer of the eye and contains blood vessels that nourish the inner parts of the eye

Question 4

What is the function of the iris?

Answer 4

Regulates the amount of light entering the eye by adjusting the size of the pupil

Question 5

When does pupil dilation occur?

Answer 5

In low light conditions, the pupil enlarges to allow more light to enter the eye and improve vision in dim light. Activates the sympathetic nervous system.

Question 6

When does pupil constriction occur?

Answer 6

In bright light conditions, the pupil becomes smaller to reduce the amount of light entering the eye and to avoid damage to the retina.

Accommodation reflex : when the eye is focusing on a close object

Question 7

What is accommodation?

Answer 7

The ability of the eye to focus on distant and nearby objects by changing the focal length

Question 8

What is the aqueous humour?

Answer 8

Viscous liquid filled in the area between the cornea and eye lens
Prevents the eye from collapsing due to changes in atmospheric pressure

Question 9

What is the retina?

Answer 9

Delicate membrane having a large number of light-sensitive cells and it is situated at the back of the inner eye.

Question 10

What are the 2 types of light sensitive cells?

Answer 10

Rod cells - responds to the intensity of light
Cone cells - responds to the color of the objects

Question 11

What is the fovea?

Answer 11

Center of the eyes sharpest vision and location of most colour perception.
Maximum number of cones are present.

Question 12

What is the optic disk?

Answer 12

Aka the blind spot, it is insensitive to light. It is a small region in the retina where the optic nerve enters the eye.

Question 13

Which part of the brain does the impulses from the eye travel to?

Answer 13

The thalamus
The occipital lobe - visual processing

Question 14

What are the 2 streams in visual processing?

Answer 14

Ventral stream
Dorsal stream

Question 15

What is the ventral stream?

Answer 15

“what” stream - involved in object processing such as color, texture, pictorial detail, shape and size

Question 16

What is the dorsal stream?

Answer 16

“where” stream
Involved ion spatial processing such as location, movement, spatial transformations and spatial relations

Question 17

What happens if there’s damage to the ventral stream?

Answer 17

Impairs contrast sensitivity, form and color vision and depth perception.

Question 18

What happens if there is a damage to the dorsal stream?

Answer 18

Spatial disorders such as simultanagnosia and optic ataxia

Question 19

What do cones do?

Answer 19

Enable the perception of fine detail and color

Question 20

Where are cones found?

Answer 20

Central region of the retina

Question 21

What do rods do?

Answer 21

Responsible for vision in low-light conditions, detecting movement and providing peripheral vision.

Question 22

Where are rods found?

Answer 22

Around the periphery of the retina

Question 23

What kind of vision do humans have?

Answer 23

Trichromatic vision

Question 24

What is tetrachromatic vision?

Answer 24

People who have 4 or more types of cones

Question 25

What is monochromacy?

Answer 25

People see the world in grayscale