l06 eye and ear

Question 1

what is the pupil

Answer 1

opening in the middle of the eye which light passes through

Question 2

what is the iris

Answer 2

visible coloured ring at the front of the eye adjusts to control the amount of light entering the eye.

Question 3

what are tear glands

Answer 3

produce tears to clean and lubricate the front of the eye
fluid contains salt and natural antiseptic properties to defend against infection

Question 4

what is the aqueous and vitreous humours

Answer 4

are the watery, jelly-like fluids that fill the eye
keep the eye in shape and nourish it

Question 5

what is conjuctivia

Answer 5

thin membrane that protects the cornea

Question 6

what is the retina

Answer 6

inner lining of the eye, contains light sensistive cells called roads and cones

Question 7

what is macula

Answer 7

high concentration of photoreceptor cells which detect light and send signals to the brain, interprets them as images

Question 8

what is the optic nerve

Answer 8

where nerve cells exit the eye
there are no rods or cones there and so this is called the blind spot

Question 9

what is cilary muscle

Answer 9

enables the lens to change shape for focusing
contracts to stretch the lens making it flatter and thinner

Question 10

what are the suspensory ligaments

Answer 10

attach the lens to the cilary muscle

Question 11

what is the lens

Answer 11

focuses light entering the eye

Question 12

what are the 4 malfunctions of the eye

Answer 12

cataracts, glaucoma, retinopathy, AMD

Question 13

what are the causes if cataracts

Answer 13

diabetes
exposure to ultraviolet light
taking long term medication like statins
family history
smoking and drinking too much

Question 14

effects on the eye of cataracts

Answer 14

change in lens, caused by ageing usually and cloidy patches develop in lens
bluurred cloudy or misty vision
colours look pale and less clear
everything have brown or yellow tinge
small patches of less visable vision
double vision
lights uncomfortable to look at, dazzling

Question 15

causes of retinopathy

Answer 15

complication of diabetes, caused by high blood pressure what damages the retina, well controlled diabetes even sgtill causes blood sugar levels to cause blood vessels to narrow and leak. result in abnormal blood flow to retina, damages cells

Question 16

effect on eye of retinopathy

Answer 16

can cause blindness if undiagnosed and untreated

Question 17

possible causes of glaucoma

Answer 17

build up of pressure in eye when fluid from aqueous humour is unable to drain, inctreases pressure and damage optic nerve

can increase risk by age, ethnicity, family history, medical conditions ie diabetes

Question 18

effects on eye of glaucoma

Answer 18

doesn’t usually cause symptoms to begin with develops slwoly over years and effects peripheral vision first
blurred vision, seeing rainbow coloured circles around some bright lights
if left untreated build up of fluid presses on optic nerve and destroys it eventually causing blindness

Question 19

causes of age related macular degeneration (AMD)

Answer 19

unknown
linked to smoking, high blood pressure, being overweight and having family history of condition

Question 20

effects on eye of Age related macular degeneration (AMD)

Answer 20

• doesn’t cause total blindness, make activities hard like reading and recognises faces, loss of central vision
  without treatment gets worse and happens gradually
  straight lines look wavy of crooked
  objects look smaller than normal
  colours seem less bright than they used to
  seeing things that aren’t there (hallucinations)

Question 21

what is the eardum structure

Answer 21

thin layer of tissue that receives sound vibrations and transmits them to the middle ear cavity

Question 22

what is the stapes/ incus/ mallous ear bone structure (stirrup, anvil and hammer)

Answer 22

small bones which amplify the sound waves and transmit the vibrations across the middle of the ear to the cochlea

Question 23

what is the cochlea ear structure

Answer 23

contains jelly like fluid in a coiled tube that resembles a snails shell, vibrations pass through the fluid and are converted into neural messages and passed onto the brain via the auditory nerve

Question 24

what is the organ of corti ear structure

Answer 24

located in cochlea and is sometimes called bodys microphone and is lined with rows of hair cells that convert sound vibrations into the nerve impulses

Question 25

what is the eustachian tube structure

Answer 25

connects the midldle of the ear to the throat, ensures the pressure in the middle is equal to the pressure outside of the ear

Question 26

what is the round window structure

Answer 26

drum like membrane, vibrations from the oval window pass through it to the cochlea

Question 27

what is the auditory nerve structure

Answer 27

bundle of thick fibres which carry hearing information between the cochlea and the brain

Question 28

what is the semi circular canals and ampullae structure

Answer 28

tiny fluid filled tubes in the inner ear which helps with balance, they have nothing to do with the hearing, lined with cilia and as the movements of the cilia are communicated to the brain they work as a kind of motion sensor to help to keep your balance