the senses - the eye definitions

Question 1

conjunctiva

Answer 1

thin membrane that protects the sclera

Question 2

sclera

Answer 2

white of the eye
holds eye in shape, protection

Question 3

cornea

Answer 3

transparent part of the sclera
lets light in and bends it towards retina

Question 4

chorid layer

Answer 4

contains blood vessels - nourishment
contains melanin to absorb light in the eye

Question 5

retina (light sensitive)

Answer 5

light receptors (rods+cones)

Question 6

rods

Answer 6

detect black and white
work in dim light
all over retina

Question 7

cones

Answer 7

detect colour
bright light
mostly in fovea

Question 8

rods pigment

Answer 8

rhodopsin

Question 9

cones pigment

Answer 9

iodospin

Question 10

fovea

Answer 10

only cones
region of sharpest vision
images are focused

Question 11

blind spot

Answer 11

nerve fibres leave the eye here
no rods or cones

Question 12

optic nerve

Answer 12

carries impulses to brain

Question 13

lens

Answer 13

focuses light on retina

Question 14

ciliary muscle

Answer 14

changes shape of lens (reflex action)

Question 15

leis

Answer 15

coloured part of eye
controls part of light entering eye

Question 16

pupil

Answer 16

opening in iris
lets light into eye
black - no light emerges from inside the eye

Question 17

aqueous humour

Answer 17

holds front of eye in shape

Question 18

vitreous humour

Answer 18

supports eye by exerting on outward pressure on eyeball

Question 19

external muscle

Answer 19

6 external muscles move the eye