Microsoft Word libs task oosci 11 5090 12 2022

6
The graph shows the effect of varying pH values on the activity of four different enzymes, 
A
, 
B
, 
C
and 
D
. 
Which enzyme is active in the stomach? 
0
2
4
6
8
10
12
14
rate of
enzyme
activity
pH
A
B
C
D
7
A small mountain lake has aquatic plants growing under water on the lake bed. Shortly after 
heavy rainfall, the mud on the lake bed becomes stirred up and the water level rises. 
Why does this cause the rate of photosynthesis of these plants to fall? 
A
extra carbon dioxide 
B
extra dissolved nitrates 
C
lower light intensity 
D
lower oxygen concentration 
8
The graph shows how the yield of a wheat crop varies with the addition of different amounts of 
nitrate fertiliser. 
yield
amount of nitrate fertiliser added
What can be concluded from the graph? 
A
Nitrates help the formation of chlorophyll in wheat leaves. 
B
The yield of wheat is proportional to the amount of nitrate fertiliser added. 
C
Nitrate is needed for the formation of proteins. 
D
Nitrates are required for healthy plants, but excess nitrates may inhibit growth. 

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5
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5090/12/O/N/22 
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9
A lack of certain minerals and vitamins can lead to deficiency diseases. 
Which row shows the correct symptoms of such diseases? 
deficiencies in diet 
symptoms in body 
A 
calcium and vitamin C 
too few red blood cells and deformed bones 
B 
calcium and vitamin D 
brittle bones and bleeding gums