MEDIUM
Upper Secondary-IGCSE
IMPORTANT
Earn 100

Part of leaf                                           Sun leaf                           Shade leaf                       
Cuticle    
Palisade mesophyll               Longer  Shorter
Spongy mesophyll    

Suggest an explanation for the difference in the palisade layer that you have described in the above table 

Important Questions on Plant Nutrition

MEDIUM
Upper Secondary-IGCSE
IMPORTANT
Biology for Cambridge IGCSE Workbook 4 th Edition Digital Access>Chapter 6 - Plant Nutrition>Exercise 6.2>Q 8

An experiment was performed to find out how fast a plant photosynthesised as the concentration of carbon dioxide in the air around it was varied. The results are shown in the table

Percentage concentration of carbon dioxide Rate of photosynthesis /arbitrary units
0.00 0
0.02 33
0.04 53
0.06 68
0.08 79
0.10 86
0.12 89
0.14 90
0.16 90
0.18 90
0.20 90

Plot these results on the grid below and draw a line.

 

MEDIUM
Upper Secondary-IGCSE
IMPORTANT
Biology for Cambridge IGCSE Workbook 4 th Edition Digital Access>Chapter 6 - Plant Nutrition>Exercise 6.2>Q 9

Explain why the rate of photosynthesis increases as carbon dioxide concentration increases.

MEDIUM
Upper Secondary-IGCSE
IMPORTANT
Biology for Cambridge IGCSE Workbook 4 th Edition Digital Access>Chapter 6 - Plant Nutrition>Exercise 6.2>Q 10

The experiment was repeated at a lower light intensity. The results are shown in the table. Plot these values on your graph and draw a line. Label the two lines.

Percentage concentration of carbon dioxide Rate of photosynthesis /arbitrary units
0.00 0
0.02 20
0.04 29
0.06 35
0.08 39
0.10 42
0.12 45
0.14 46
0.16 46
0.18 46
0.20 46
MEDIUM
Upper Secondary-IGCSE
IMPORTANT
Biology for Cambridge IGCSE Workbook 4 th Edition Digital Access>Chapter 6 - Plant Nutrition>Exercise 6.2>Q 12

An experiment was performed to find out how fast a plant photosynthesised as the concentration of carbon dioxide in the air around it was varied. 

The experiment was performed at a lower light intensity. The results are shown in the graph. Use the graph to determine the rate of photosynthesis in normal air in higher light intensity.

 

MEDIUM
Upper Secondary-IGCSE
IMPORTANT
Biology for Cambridge IGCSE Workbook 4 th Edition Digital Access>Chapter 6 - Plant Nutrition>Exercise 6.2>Q 13
Up to what concentration is carbon dioxide a limiting factor for photosynthesis in low light intensity?
MEDIUM
Upper Secondary-IGCSE
IMPORTANT
Biology for Cambridge IGCSE Workbook 4 th Edition Digital Access>Chapter 6 - Plant Nutrition>Exercise 6.2>Q 14
Above 0.04% concentration, what is the limiting factor for photosynthesis when the plant is exposed to low light intensity?
MEDIUM
Upper Secondary-IGCSE
IMPORTANT
Biology for Cambridge IGCSE Workbook 4 th Edition Digital Access>Chapter 6 - Plant Nutrition>Exercise 6.2>Q 15

Farmers and market gardeners often add carbon dioxide to the air in glasshouses where crops are growing. Use above graph to explain the advantage of doing this.

MEDIUM
Upper Secondary-IGCSE
IMPORTANT
Biology for Cambridge IGCSE Workbook 4 th Edition Digital Access>Chapter 6 - Plant Nutrition>Exercise 6.2>Q 16
It is expensive to add carbon dioxide to glasshouses. Suggest a suitable concentration of carbon dioxide to add to a glasshouse in high light intensity, to obtain a good financial return from the sale of the crop. Explain your answer.