Page 39 - 新思维科学学生用书6 样章

1 The human body

Look what I can do!

I can name types of living things that cause diseases.

I can find information about diseases.

I can say how our body stops us from getting infectious diseases.
I can describe things we can do to prevent diseases from spreading.

I can group methods to prevent diseases.
I can draw a dot plot of results.

I can say how to avoid being bitten by insects.

Project: The circulatory system

Part 1: Discovery of how the circulatory system works
People have tried to explain

how the circulatory system

works for more than two
thousand years. One of

the main books of Chinese

medicine, written 2600 years
ago, stated that ‘all of the

blood in the body is pumped
by the heart, completes a circle

and never stops moving’.

Galen was a surgeon and doctor who lived in what is now modern-day Turkey
about 1900 years ago. At that time, scientists already knew that there were two

types of blood vessels in the body – arteries and veins. Galen thought that the
liver produced blood, which was then carried to the rest of the body in the veins.

The body then used up the blood for energy as it flowed to the different organs.

Galen also stated that the arteries contained blood, not air, which was what earlier
scientists had thought. He understood that blood went from one side of the heart

to the other side of the heart, but he didn’t know how that happened. He thought

there were tiny holes in a wall between two sides of the heart.

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