Sight

Question 1

What is the conjunctiva?

Answer 1

A thin membrane protecting the sclera

Question 2

What is inflammation of the conjunctiva called?

Answer 2

Conjunctivitis

Question 3

What is conjunctivitis?

Answer 3

Inflammation of the conjunctiva

Question 4

What is the sclera?

Answer 4

The white of the eye

Question 5

What is the sclera also called?

Answer 5

The sclerotic coat

Question 6

What is the function of the sclera?

2 points

Answer 6

It lets no light through as it is very tough and opaque

It holds the eye in shape

Question 7

What is the choroid?

Answer 7

A dark-coloured layer which contains blood vessels which nourishes the eye and melanin which absorbs light in the eye

Question 8

What is the function of the choroid?

Answer 8

Ensures that there is no internal reflection of light inside the eye.

Question 9

What is the function of the retina?

Answer 9

Contains light receptors (cones/rods)

Question 10

How many rods are found in the eye?

Answer 10

120 million per eye

Question 11

How many cones are found in the eye?

Answer 11

6 million per eye

Question 12

What is the function of rods?

Answer 12

Detects black and white light

Question 13

What is the function of cones?

Answer 13

Detects colours

Question 14

What type of light do rods work in?

Answer 14

Dim light

Question 15

What type of light do cones work in?

Answer 15

Bright light

Question 16

Where are rods found in the retina?

Answer 16

All over the retina

Question 17

Where are cones found in the retina?

Answer 17

Mostly at the fovea

Question 18

What is the fovea?

3 points

Answer 18

The are of the retina where only cones are found
It is the region of sharpest vision
Most images are focused here

Question 19

What is the fovea also called?

Answer 19

The yellow spot

Question 20

What is the blind spot?

4 points

Answer 20

A part of the retina where nerve fibres leave the eye
There are no cones or rods found here.
It is not sensitive to light
The area of the eye where vision is obstructed due to nerve fibres of rods and cones impeding incoming light rays

Question 21

What is the optic nerve?

Answer 21

The area of the eye where 126 million axons are found which carry impulses from the rods and cones to the cerebrum

Question 22

What is the lens?

Answer 22

An elastic, transparent structure which changes shape to focus light on the retina.

Question 23

What is the ciliary muscle?

Answer 23

Muscle which surrounds the lens

Causes the shape of the lens to change when looking far away or close

Question 24

What is the changing of the shape of the lens called?

Answer 24

accommodation

Question 25

What connects the ciliary muscle to the lens?

Answer 25

Suspensory ligaments

Question 26

What is the iris?

Answer 26

The coloured, muscular part of the eye which controls the amount of light entering the eye
May be pigmented with melanin (eye colour)

Question 27

What is the pupil?

Answer 27

The opening in the iris which lets light into the eye

It is black as no light emerges from the inside of the eye

Question 28

What happens to the size of the pupil in bright light?

Answer 28

Its size reduces to let less light enter the eye

Question 29

What happens to the size of the pupil in dim light?

Answer 29

Its size increases to let more light enter the eye.

Question 30

What is the aqueous humour?

Answer 30

A salt solution which holds the front of the eye in place

Question 31

What is the vitreous humour?

Answer 31

A viscous solution which supports the eye by exerting an outward pressure on the eyeball

Question 32

What are the external muscles?

Answer 32

Six muscles which control the movement of the eye