Sensory systems

Question 1

What is the pupil?

Answer 1

It is the opening in the middle of the eye which is often black. Light passes through this

Question 2

What is the iris?

Answer 2

the visible coloured ring at the front of the eye

Question 3

Why does the iris adjust?

Answer 3

To control the amount of light entering the eye through the pupil

Question 4

What are tear glands?

Answer 4

AKA lacrimal glands

produce tears to clean and lubricate the front of the eye

Question 5

What does the fluid found in tear glands contain?

Answer 5

Salt and natural antiseptic properties which defend against infection

Question 6

What are aqueous and vitreous humours (fluids)?

Answer 6

Watery, jelly like fluids that fill the eye.

Question 7

What do aqueous and vitreous humours do?

Answer 7

They keep the eye in shape and nourish it

Question 8

What is the conjunctiva?

Answer 8

A thin membrane that protects the cornea

Question 9

What is the cornea?

Answer 9

A transparent film through which light rays pass into the retina of the eye.

Question 10

Where is the cornea found ?

Answer 10

At the front of the eye

Question 11

What is the retina?

Answer 11

The inner lining of the eye which contains light sensitive cells called rods and cones

Question 12

macula

Answer 12

Has a very high concentration of photoreceptor cells

Question 13

What do macula detect?

Answer 13

It detects light and sends signals to the brain which interprets them as images.

Question 14

What is the optic nerve?

Answer 14

It is where the nerve cells exit the eye.

Question 15

Why is the optic nerve known as the blind spot?

Answer 15

Because there are no rods or cones

Question 16

What is the ciliary muscle?

Answer 16

A muscle that enables the lens to change shape for focusing

Question 17

How does the cilliary muscle stretch the lens?

Answer 17

By contracting

Question 18

By contracting, what does the ciliary muscle become?

Answer 18

Flatter and thinner

Question 19

What do suspensory ligaments do?

Answer 19

Attach the lens to the ciliary muscle

Question 20

What does the lens do?

Answer 20

It focuses the light entering the eye

Question 21

What is the eardrum known as?

Answer 21

tympanic membrane

Question 22

What is the eardrum and what does it do?

Answer 22

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

Question 23

What are the following also known as?
Stapes
incus
malleus ear bones

Answer 23

stirrup
anvil
hammer

Question 24

What are the stapes incus and malleus ear bones?

Answer 24

Small bones

Question 25

What do the stapes incus and malleus ear bones do?

Answer 25

Amplify sound waves and transmit the vibrations across the middle of the ear to the cochlea

Question 26

What is the cochlea?

Answer 26

Coiled tube that contains jelly like fluid. Vibrations pass through the fluid and are converted to neural messages. The vibrations are then passed on to the brain via the auditory nerve.

Question 27

Where is the organ of Corti located?

Answer 27

In the cochlea

Question 28

What is the organ of Corti sometimes called and why?

Answer 28

Sometimes called the body's microphone and is lined with rows of hairs that convert sound vibrations into nerve impulses

Question 29

What is the Eustachian Tube?

Answer 29

A tube that connects the middle of the ear to the throat

Question 30

What is the Eustachian Tube's role?

Answer 30

It ensures that the pressure in the middle of the ear is equal to that outside of thee ear

Question 31

What is the round window?

Answer 31

A drum like membrane

Question 32

What happens to the vibrations from the oval window?

Answer 32

Vibrations pass through the round window to the cochlea

Question 33

What is the auditory nerve?

Answer 33

It is a bundle of nerve fibres

Question 34

What is the role of the auditory nerve?

Answer 34

It carries hearing information between the cochlea and the brain

Question 35

What are semi-circular canals and ampullae?

Answer 35

They are tiny fluid filled tubes in the inner ear that help with balance

Question 36

What are the semi-circular canals and ampullae lined with and what do these act as?

Answer 36

They are lined with cilia. The movements of these cilia are communicated to the brain. As they do this they act as a motion sensor allowing you to keep your balance.

Question 37

What do semi-circular canals and ampullae have nothing to do with?

Answer 37

Hearing

Question 38

Name four malfunctions of the eye...

Answer 38

Glaucoma Age related macular degeneration Cataracts Retinopathy

Question 39

Name the three different types of hearing loss....

Answer 39

Gradual hearing loss Conductive hearing loss Sensorineural hearing loss

Question 40

What is glaucoma caused by?

Answer 40

A build up of pressure in the eye when fluid from the aqueous humour is unable to drain properly.

Question 41

What does a build up of pressure in the eye lead to?

Answer 41

Damage to an optic nerve

Question 42

What can increase the risk of getting glaucoma?

Answer 42

Age - more common as you get older Ethnicity - people of African, Caribbean or Asian origin are at higher risk Family history - more likely to develope it if a parent or sibling has the condition Other medical conditions like diabetes make you more susceptible to having glaucoma

Question 43

What is the cause of age related macular degeneration?

Answer 43

``` Exact cause = unknown however it is linked to... - smoking - high blood pressure - Being overweight - Family history of the condition ```

Question 44

What are the possible causes of cataracts?

Answer 44

- Diabetes - Exposure to ultraviolet light in sunlight - Taking particular medications like corticosteroids or statins, for a long time - Smoking and drinking too much alcohol - A family history of cataracts

Question 45

What is the possible cause of retinopathy?

Answer 45

It is a complication of diabetes caused by high blood sugar levels which damages the retina.

Question 46

Even in well controlled diabetes what can cause blood vessels to narrow and leak?

Answer 46

High blood sugar levels

Question 47

What do high blood levels cause to happen for those with retinopathy?

Answer 47

Damage to the cells in the retina due to the abnormal blood flow that results from a leaky blood vessel.

Question 48

What can cause gradual hearing loss?

Answer 48

Ageing or exposure to loud noises over many years

Question 49

What causes conductive hearing loss?

Answer 49

Due to a blockage by earwax or infection because of a build up of fluid or due to a perforated ear drum Possible to be caused by changes of oestrogen levels in women, in pregnancy or through genetic disposition.