8ld - The Ear Slb

The Ear 8Ld

Learning Objectives • Recall the names and positions of the main parts of the ear. • Recall that the ear changes sound energy to electrical energy that are translated by the brain into sounds. • Describe how ears can be damaged by loud sounds. • Describe how sound causes the eardrum to vibrate. • Explain how animals use ultrasound.

Hearing • In groups of 3 or 4 • Write down words to do with the topic of ‘hearing’ on post-it notes. • Once you have 10-30 words group them under your own headings/groups.

Ear bones

Ear drum Ear canal

Worksheet – 8Ld/4

In groups • There is a labelled diagram on my desk. • Each person will have a number and will be given a minute to remember as much as they can from the diagram, then take this information back to their groups. The first group to correctly complete the diagram in as much detail as possible will be awarded stickers.

2

3

4 Ear bones

B

C

D

E

1

A

Ear drum Ear canal

5

6

AT video clip – pg 169

Your ears change sound into electrical signals which are sent to your brain.

Questions 1. What energy changes happen in your ear? 2. Which part of the ear: a) detects the sound waves? b) sends messages to the brain? c) passes the vibrations from the ear drum to the cochlea? 6. a) List the parts of the ear and the jobs that they do. b) Use this information to make a flow chart to show how sounds are heard.

Ear damage The ear is very delicate. It contains thin membranes and tiny bones which are easily damaged. What are the ways you think this can happen?

Ear damage can happen by… • Getting blocked with wax. This stops the ear drum being able to vibrate properly. This can be cleaned or washed out. • Accidents or a loud bang. This can damage the ear drum, it may or may not be able to fix itself. • The middle ear becoming infected. This can be cured by antibiotics. • The bones fusing together in old age. This prevents vibrations from becoming bigger. • The nerve cells in the cochlea not working very well as you get older. This means the messages are not sent to the brain. • The cochlea being affected by loud noise, from loud nightclubs and personal stereos. There is no cure for this.

Practical – Are two ears better than one for determining direction of sound? • Discuss this in groups – we will put ideas up on the board. • Get into groups of 9/10. One person sits in the centre with a blindfold. The others sit evenly around. One person must clap and the person sat in the middle points in their direction. • Repeat using one ear plug. • Which way is easier?

Sound waves • Vibrating sound waves travel through the _____ and into the ear., making the ____ _____ vibrate. • When the ______ waves reach the c_____ they are changed into ________ signals called impulses. Which travel down a nerve into the brain. • When the _______ reach the brain we hear the sound. Impulses, air, signal, electrical, cochlea, ear drum

Sound waves • Vibrating sound waves travel through the air and into the ear., making the ear drum vibrate. • When the sound waves reach the cochlea they are changed into electrical signals called impulses. Which travel down a nerve into the brain. • When the impulses reach the brain we hear the sound.

Learning Objectives • Recall the names and positions of the main parts of the ear. • Recall that the ear changes sound energy to electrical energy that are translated by the brain into sounds. • Describe how ears can be damaged by loud sounds. • Describe how sound causes the eardrum to vibrate. • Explain how animals use ultrasound.