Editorial Development: Bonnie Brook Communications

A Look at Hearing
When there is a noise, sound waves travel 
through the air to the ear canal in the outer ear. 
Once there, the waves cause the tympanic 
membrane (commonly called the eardrum) to 
vibrate. This membrane is very sensitive to 
vibrations. When the eardrum moves, it touches 
the first of three tiny bones called ossicles in the 
middle ear. One by one, the ossicles transfer the 
vibrations to the inner ear, where they move 
over small hairs on the cochlea. This causes the 
auditory nerve to send signals to the brain. The 
brain then interprets the signals as sound. 
SKILL PRACTICE
Read each question. Fill in the bubble next to the correct answer.
 1. What part of the ear blocks out water and
foreign matter?
A 
the tympanic membrane
B 
the ear canal
C 
the ossicles
D 
the pinna
 2. Which of the following best describes the shape
of the cochlea?
A 
a bean
B 
a wishbone
C 
a straw
D 
a snail shell
 3. Which part of the ear transfers vibrations directly 
to the cochlea?
A
 
the stirrup 
B
 
the hammer
C
 
the tympanic membrane
D
 
the auditory nerve
 4. Which part of the ear does something other than 
transmit sound waves?
A 
the cochlea
B 
the auditory nerve
C 
the ossicles
D 
the eustachian tube
STRATEGY PRACTICE
Which information from the passage and the diagram would you use if you had to 
explain the process of hearing sound in only three steps? Why?
 
Eardrum
Ear Can
al
Eustachian Tube