Ear

Question 1

illustrate a large diagram of the internal structure of the ear

Answer 1

see diagram in manual

Question 2

what does the middle ear consist of

Answer 2

ear ossicles, oval window, round window and eustachian tube

Question 3

what does the outer ear consist of

Answer 3

pinna, auditory canal and eardrum

Question 4

what does the inner ear consist of

Answer 4

cochlea and semi circular canals

Question 5

suggest one way by which the ear may be protected

Answer 5

• by the skull
• wax
• wearing ear protection

choose any one or can just learn all off

Question 6

structure and function of the pinna

Answer 6

• the pinna is skin converted cartilage

- it’s role is to collect sound waves and direct them to the auditory canal

Question 7

structure and function of the auditory canal

Answer 7

• the auditory canal is a short curved tube extending from the pinna to the eardrum. secretes ear wax for protection
• it’s role is to carry sound waves to the eardrum. The ear wax keeps canals clean and so protects the ear

Question 8

structure and function of the eardrum

Answer 8

• the eardrum is a tightly stretched membrane which separates the outer ear from the middle ear
• it’s role is to vibrate same frequency as sound waves reaching it and transfers these vibrations to the ear ossicles of the middle ear

Question 9

structure and function of the ear ossicles

Answer 9

• the ear ossicles are three tiny bones which connect the ear drum to the oval window
• it’s role is to transfer and amplify vibrations of the eardrum to the oval window

Question 10

structure and function of the oval window

Answer 10

• the oval window separates the air filled middle ear from the liquid filled inner ear
• it’s role is to transfer vibrations of the stirrup to the cochlea ** this sets up pressure waves in the cochlea

Question 11

structure and function of the eustachian tube

Answer 11

• this tube is connected to the pharynx and is normally closed. it’s opened we swallow and yawn
• it’s role is to equalise air pressure on either side of the ear drum

Question 12

function of the round window

Answer 12

-it’s role is to dampen the pressure changes in the cochlea so that one can hear many sounds clearly in quick succession

Question 13

Structure and function of the cochlea

Answer 13

• the cochlea is a spiral bony chamber filled with lymph
• it’s role is to generate nerve impulses from pressure waves

a. Contains sound receptors which are stimulated by the movement of lymph
b. Receptors generate an impulse which is sent to the brain through the auditory nerve
c. The brain interprets impulse as sound

Question 14

Role of semi circular canals

Answer 14

-balance is controlled by the vestibular apparatus it consists of the semicircular canals nerve impulses are generated inside these semicircular canals

Question 15

why are there three semicircular canals

Answer 15

to control balance in three planes

Question 16

What is the role of the cochlea

Answer 16

Generates impulses

Question 17

Describe the mechanisms of hearing

Answer 17

1. Vibrations are collected in the outer ear
2. These vibrations pass through the middle ear and are amplified by the ear ossicles
3. Vibrations reach the cochlea and create pressure waves in the lymph of the cochlea
4. Receptors in the cochlea are stimulated and these then create impulses
5. The auditory nerve tranmits impulses to the brain
6. The brain interprets impulse as sound
7. The round window allows pressure waves to leave the cochlea and pass into the air filled middle ear

Question 18

Name a disorder associated with the ear along with the description and corrective measure

Answer 18

Disorder : glue ear

Description: inflammation of the middle ear
-results from bacterial infection

Corrective measure: antibiotics