Page 46 - 新思维科学学生用书9 样章

1 Photosynthesis and the carbon cycle

b Match each of these labels to the correct number on the diagram.

i feeding
ii combustion
iii photosynthesis [2]
c Name one compound found in plants that contains carbon. [1]

1.5 a Carbon dioxide concentration in the atmosphere is increasing.
This is causing the Earth’s climate to change.
Choose the statements that describe predicted future impacts

of climate change.
• The mean temperature at the North and South Poles will decrease.
• Sea level will rise.
• There will be more extreme weather events, such as typhoons and

hurricanes.
• There will be less sunlight reaching the surface of the Earth. [1]
b In the past, asteroids have collided with the Earth. Scientists believe
this has caused mass extinctions.
i Explain what is meant by a mass extinction. [1]

ii Explain how an asteroid collision can cause mass extinctions. [3]

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