Study Guide for Hearing and Sound Check Up
Test will be on Thursday, February 20, 2013
We are at the end of our Hearing and Sounds unit and your child will be taking their final Check Up for this unit
within the next few weeks. Please study the following information with them. We have had a variety of discussions,
experiments, group projects, and worksheets on each of the topics below. By giving this to your child early, they
will have plenty of time to come and ask me any questions that they may have prior to February 20th.
1. Outer Ear: Consists of the Pinna and the Ear Canal
2. Middle Ear: Consists of the Eardrum and the Ossicles (the three tiny bones: Hammer, Anvil, and
Stirrup) Hint: The order of the bones can be remembered by one word: H-A-S.
3. Inner Ear: Consists of the Cochlea and the Auditory Nerve
How is Sound Created and How Do We Hear it?
Sound is created when something vibrates. The vibrating object causes the air around it to vibrate. This vibration
travels through the air and to your pinna. Your pinna catches the sound waves and funnels it into your ear canal.
Your ear canal acts as a passageway, allowing the sound wave to travel to your eardrum. Your eardrum vibrates
when the sound hits it, which makes the three tiny bones vibrate. The stirrup makes the cochlea vibrate, which is
full of fluid and tiny hairs. The fluid and hairs begin to vibrate and turn the vibrations into impulses, which are
passed on to your auditory nerve. Your auditory nerve then sends the impulses to your brain. Your brain makes
sense of the impulses and tells you what you are hearing.
Ways to Protect Our Ears
It is very important that we take care of our ears. When we are around loud sounds, especially those over 100 dB,
we should make sure that we cover our ears. We can wear ear protectors, use ear plugs, or even use our hands to
cover our ears. We can also protect our ears by cleaning them regularly. You should never use anything sharp to
clean your ears or you could damage your ear canal or eardrum! If you don’t protect your ears, you could become
hard of hearing or even deaf. This would mean that others may have to use sign language to communicate with you!
Do Humans and Animals Hear the Same?
Animals and humans have different hearing abilities. Remember, the bigger your pinna is, the more sound waves you
can funnel into your ear! That is why rabbits can hear so well! Also remember that some animals can hear different
frequencies and pitches. For example, dolphins and bats can hear sounds that are much higher than we can.
Important Vocabulary Words
Unpleasant Sounds: noise (any sound that is considered unwanted, unpleasant or too loud)
Pleasant Sounds: sounds that do not hurt your ears
Decibels (dB): the unit used to measure the loudness and intensity of sound
Deaf: unable to hear sounds
Pitch: the highness or lowness of a sound
Volume: the loudness or softness of a sound
Megaphone: a funnel or cone shaped device for amplifying sound or directing sound
Sound Waves: the regular patter of vibrations that move through the air, liquid, and solid (but cannot travel
through a vacuum, like space)
Echo: the bouncing or reflection of a sound wave from a surface
Frequency: the number of sound vibrations per second
Vibration: movements back and forth or up and down that create a sound
Wavelength: one full wave movement, such as from the crest of one wave to the crest of the next wave
Amplifying Sound: to increase the volume of sound or to make a sound louder
Sound Proofing: to decrease the volume of sound or to make the sound quieter and softer
Volume and Pitch