Page 44 - 新思维科学学生用书9 样章

1 Photosynthesis and the carbon cycle

Check your progress

1.1 Choose the correct word from the list to match each description.
You can use each word once, more than once or not at all.
air carbon dioxide chlorophyll chloroplast

oxygen soil stomata veins
a This gas is used by plants in photosynthesis. [1]
b This gas is made by plants in photosynthesis. [1]
c Plants get their water for photosynthesis from here. [1]

d This green pigment absorbs energy from sunlight. [1]
e These tiny holes in a leaf allow gases to diffuse in and out. [1]
1.2 Marcus did an experiment to compare

the rate of photosynthesis of two types
of seaweed. Seaweeds are plant-like
organisms that live in sea water. measuring cylinder
The diagram shows the apparatus he used. beaker
a What variable should Marcus change

in his experiment? sea water [1]
upside down
b List three variables that Marcus should funnel
keep the same. seaweed [3]
c What should Marcus measure during

his experiment? [2]
1.3 A farmer carried out 8
an experiment to

find out how adding
different quantities 6
of nitrate- containing Grain yield in
fertiliser affected the tonnes per hectare

quantity of grain that 4
she harvested from her
wheat crop. The graph
shows the results.
2
0 20 40 60 80 100 120 140 160
Fertiliser used in kg per hectare

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