Page 31 - 新思维科学学生用书9 样章

1 Photosynthesis and the carbon cycle

It is important to remember that fossil fuels are not the same as fossils. A fossil is the remains of an Continued

organism, or traces of it (such as its burrows) that have turned to rock. We can still see the shape of
the organism in a fossil. But fossil fuels do not look like organisms at all, and oil and gas are not even the correct place. For example, if the number is 1, then all the carbon atoms in the air
rocks. Fossil fuels are given this name because – like fossils – they were formed a very long time ago move into a green plant, as a result of photosynthesis. If the number is 3, then all the
and buried underground. carbon atoms in a green plant move into an animal.
You can keep a record of how many carbon atoms are in each place after each roll of

Activity 1.3.1 the die.
Questions
Modelling the carbon cycle
In this activity, you will play the part of a carbon atom in the carbon cycle. 1 In this model, all the carbon atoms in one place move to another place at the
First, make some big labels and stick them in five different places in the room. You only same time. Is that what happens in the real carbon cycle? If not, how could you

need one set of labels for the whole class. modify this model to make it a better representation? If you can, try out your
suggestion on your model.
2 Predict what would happen to the carbon atoms if one of the processes

stopped completely – for example, combustion. If you can, try it out on your
model.

The carbon cycle is a complicated diagram. What can you do to help you to
remember it?

Now write the following numbers and what they mean on the board, where everyone
will be able to see them from every part of the room: Questions

1 photosynthesis
2 respiration

3 feeding

4 formation of fossil fuels

5 decomposition

6 combustion.
Divide the class except one person (who could be your teacher) between the five
places. Each person is a carbon atom.

The one person who is not a carbon atom now holds a die. (A die is a cube with the
numbers 1 to 6 on it. The plural is dice.) They roll it, and call out the number. All the
carbon atoms who are affected by the process linked to this number, move to

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