Page 35 - 新思维科学学生用书6 样章

1 The human body

Activity 1

Find information about diseases

Do some research to find out the following:

• the word we use to describe any living thing that causes a disease

• the names of the parasites that cause malaria and dysentery
• how the parasites that cause malaria and dysentery are spread.

The body’s defences against diseases

Our bodies have different ways to stop us from being infected with diseases.
We call these the body’s defences against diseases.

There are bacteria
and other living organisms
all around us that
cause disease.

So why are we
not ill all the time?

Tears contain a chemical
substance that kills some
bacteria

Mucus in the nose, windpipe
and other air passages is
sticky and traps germs

Skin acts as a barrier to
stop germs from getting
into the body

Acid in the stomach kills
germs in the food we
have eaten

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