The Eye and the Ear

4. gelatinous substance which nourishes eye and helps it hold its shape
7. photoreceptor which is more sensitive in less light
10. transparent structure in the front of the eye which helps focus light
11. specialised part of a sensory nerve which detects a stimulus
13. outer ear structure which directs sound down the external auditory canal
15. transparent liquid at the front of the eye, maintains pressure
16. the organ of hearing, inside the cochlea, where the auditory receptors are found
18. transfers residual energy from cochlea to eustachian tube to balance pressure
19. three small bones in middle ear which transfer sound energy (anvil, hammer and stirrups)
21. ability to feel external (or internal) stimulus
22. muscles which help alter shape of lens

1. structure in eye which can focus light from objects at different distances
2. dark membrane behind retina containing blood vessels
3. structure in inner ear which help sense head position (for balance)
5. the white outer layer of the eye
6. photoreceptor (3 types in human) which allows colour vision
8. area of retina where blood and nerves enter/exit eye
9. ability to interpret/respond to a stimulus
12. aka macula, area opposite centre of cornea which has highest density of photoreceptors
14. aka ear drum, vibrates in response to sound waves entering the auditory canal
16. transfers sound energy to the cochlea
17. structure in inner ear where sound is sensed
18. found at back of the eye containing photoreceptors
20. coloured structure at front of eye which dilates or constricts pupil
21. something which activates a receptor