Eye

Question 1

What liquid fills the anterior chamber?

Answer 1

Aqueous humor

Question 2

What is the function of aqueous humor?

Answer 2

Maintain the shape of cornea - by pressure

A source of nutrients for non - vascular lens and cornea

Question 3

What is conjunctiva?

Answer 3

Thin mucous membrane lining the posterior surface of each eyelid and covers the sclera - contains goblet cells

Question 4

What is the function of conjunctiva?

Answer 4

Lubrication of the eye by producing mucus and tears

Prevents entry of microbes to the eye

Question 5

What is the function of sclera?

Answer 5

providing attachment for the extraoccular muscles that move the eyeball

Question 6

What is the sclera?

Answer 6

A fibrous protective outer layer of eye containing collagen and elastic fibres

Question 7

What is the function of the iris?

Answer 7

Control diameter and size of pupil - fibres are under autonomic control

Question 8

What type of iris fibres constrict the pupil and reduce the amount of light falling on the retina?

Answer 8

Circular fibres

Question 9

What is the function of radial fibres?

Answer 9

Dilate the pupil - increasing the amount of light falling on the retina

Question 10

What innervates the circular fibres of iris?

Answer 10

The oculomotor nerve

Question 11

What innervates the radial fibres?

Answer 11

Superior cervical ganglion

Question 12

What are the results of contraction of ciliary body?

Answer 12

The lens become rounder focusing on nearer objects

Question 13

What are the results of relaxation of ciliary body?

Answer 13

Causes the lens to flatten focusing on distant objects

Question 14

Where does reabsorption of aqueous humor occur?

Answer 14

Ciliary body

Question 15

What can problems of drainage of aqueous humor lead to?

Answer 15

Glaucoma - can damage the optic nerve which can lead to progressive loss of vision

Question 16

What are three function of the choroid layer?

Answer 16

1. Contain a dark pigment that absorbs light and reduces reflection
2. Highly vascular so nourishes outer layer of retina
3. Regulates retinal heat - assists in controlling intraocular pressure

Question 17

What is the name given to cloudy patches in the lens that make vision blurred or misty?

Answer 17

Cataracts

Question 18

What is the most posterior compartment of the eye?

Answer 18

The retina

Question 19

What is contained in the retina?

Answer 19

Photoreceptors

First and second order neurons of the visual pathway

Question 20

What are the 2 layers in the retina?

Answer 20

1. outer cell pigment layer - single layer of cuboidal epithelial cells with melanin filled microvilli extending from their inner surface
2. A multilayered neural retina

Question 21

Are there more rod cells in the retina or cones?

Answer 21

Rods

Question 22

What type of vision are Rods involved in?

Answer 22

Black and white

Question 23

What type of vision are cones involved in?

Answer 23

Colour

Question 24

Which has higher activity cones or rods?

Answer 24

Cones

Question 25

Which is more abundant at macula cones or rods?

Answer 25

Cones

Question 26

what does optic disk swelling cause?

Answer 26

Papilloedema

Question 27

What is papilloedema a sign of?

Answer 27

Raised intracranial pressure

Question 28

What is the fovea?

Answer 28

Point on the retina at which the image of the object at centre of visual axis falls

Question 29

How is the fovea specialised for visual activity?

Answer 29

Only cones are present light sensed without dispersion Hexagonal mosaic of cone cells

Question 30

Where are blood vessels that supply the retinal cells found?

Answer 30

In the choroid

Question 31

What is detached retina?

Answer 31

Retina begins to pull away from blood vessels that supply it with oxygen and nutrients - can lead to blindness