The Sense Organs

Question 1

How does the brain interpret messages sent to it?

Answer 1

Sensory neurones

Question 2

What are chemoreceptors?

Answer 2

Respond to chemicals
(E.g. taste in the tongue, smell in the nose, pH receptors in the blood)

Question 3

What are photoreceptors?

Answer 3

Respond to light
(E.g. rods and cones in the eye)

Question 4

What are mechanoreceptors?

Answer 4

Respond to physical change
(E.g. pressure receptors in the skin, sound receptors in the ear and receptors used in balance)

Question 5

What are thermoreceptors?

Answer 5

Respond to temperature change
(E.g. Heat and cold receptors in skin)

Question 6

What are proprioceptors?

Answer 6

Give information about the position and movement of the body
(E.g. stretch receptors in the muscles)

Question 7

How does the brain process taste?

Answer 7

Tongue detects taste
Taste buds are chemoreceptors
(sweet, salt, sour, bitter)
Send signals to brain (cerebrum) by sensory neurons

Question 8

How does the brain process smell?

Answer 8

Chemoreceptors in nose detect smell
Olfactory nerve carries information to the brain (cerebrum)

Question 9

How does the brain process touch?

Answer 9

Skin contains thermoreceptors
(detect hot/ cold) and mechanoreceptors
(detect pressure)

Question 10

What is the outer ear made up of?

Answer 10

Pinna and outer auditory canal

Question 11

What is the function of the pinna?

Answer 11

Funnel sound into ear
(Made of cartilage)

Question 12

What is the function of the outer auditory canal?

Answer 12

Contains hair (cilia) and wax to trap dust particles
Channels sound into middle ear

Question 13

What is the middle ear made up of?

Answer 13

Ear drum, ossicles (hammer, anvil and stirrup) and eustachian tube

Question 14

What is the function of the ear drum?

Answer 14

Transmit sound into middle ear

Question 15

What is the function of the ossicles (hammer, anvil and stirrup)?

Answer 15

Amplify sound and pass sound into the inner ear

Question 16

What is the function of the eustachian tube?

Answer 16

Tube that connects middle ear to the back of the throat
Equalise pressure between middle and outer ear so eardrum does not rupture

Question 17

What is the inner ear made up of?

Answer 17

Oval window, semi-circular canals, cochlea, round window

Question 18

What is the function of the oval window?

Answer 18

Start of the inner ear and transmits sound from middle to inner ear

Question 19

What is the function of the semi-circular canals?

Answer 19

Balance,
Arranged differently to cover 3 planes of movement,
Vestibular nerve carries information to the brain

Question 20

What is the function of the cochlea?

Answer 20

Vibrations from the oval window cause fluid to move in the cochlea,
Hair receptors called the organ of corti detect movement,
Hair receptor movement is detected by the auditory nerve (carries impulse to the brain)

Question 21

What is the function of the round window?

Answer 21

Absorbs movement of the liquid in the inner ear and dissipates pressure out of cochlea into middle ear.

Question 22

Name one disorder of the ear

Answer 22

Glue ear

Question 23

What are the symptoms of glue ear?

Answer 23

Sticky fluid build up in middle ear preventing ossicles from functioning.
Pressure difference builds between middle and outer ear, which could rupture eardrum

Question 24

Name a solution for glue ear

Answer 24

Gromits are inserted into eardrum to equalise pressure