Page 25 - 新思维科学学生用书6 样章

1 The human body

Activity 2 Do other animals get
oxygen the same way

Use books and the internet to find as we do?

out the answer to Sofia’s question.
Find information about two animals that get oxygen

in different ways to humans.

Make a poster to show the class what you find out.

We breathe in and out about 16 times every minute. The number

of times we breathe in and out in one minute is called our
breathing rate. Our breathing rates change depending on

how much oxygen our bodies need.

Think like a scientist 2

Investigate breathing rate

You will need:

a timer or watch with a second hand

1 Count the number of breaths you take per minute while at rest.
Record the measurement in a table.

2 Run on the spot for two minutes and then stop.

Count and record the number of breaths you take per minute.
3 Run on the spot for another two minutes and then stop.

Count and record the number of breaths you take per minute.

4 Wait two minutes and measure and record your breathing rate again.
Do this again after another two minutes.

5 Draw a line graph of your breathing rate.
6 a When was your breathing rate lowest?

b How did exercise affect your breathing rate?

Suggest a reason for this.
c Use your graph to predict how long it would take for your breathing rate to

get back to normal after you stopped exercising.

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