MEDIUM
AS and A Level
IMPORTANT
Earn 100

Based on the given figure, what is the colour of carotenoids? Explain.

Important Questions on Photosynthesis

MEDIUM
AS and A Level
IMPORTANT
Biology for Cambridge International AS & A Level coursebook 2nd Edition Digital Access>Chapter 13 - Photosynthesis>Questions>Q 4
Xanthophyll is yellow. Which wavelengths of light does xanthophyll not absorb?
HARD
AS and A Level
IMPORTANT
Biology for Cambridge International AS & A Level coursebook 2nd Edition Digital Access>Chapter 13 - Photosynthesis>Questions>Q 5

Discuss the similarities and differences between the absorption spectra for chloroplast pigments in figure a and the action spectrum for photosynthesis in figure b. If a composite line draws for the absorption spectra, combining all the absorption spectra for the different pigments, how similar would this line be to the action spectrum for photosynthesis? Suggest reasons for any differences.

 

HARD
AS and A Level
IMPORTANT
Biology for Cambridge International AS & A Level coursebook 2nd Edition Digital Access>Chapter 13 - Photosynthesis>Questions>Q 6
In both mitochondria and chloroplasts, an energetic electron passes along a chain of carriers and the energy released is used to synthesise ATP by chemiosmosis. Suggest why the process occurring in mitochondria is known as oxidative phosphorylation, whereas in chloroplast it is photophosphorylation.
MEDIUM
AS and A Level
IMPORTANT
Biology for Cambridge International AS & A Level coursebook 2nd Edition Digital Access>Chapter 13 - Photosynthesis>Questions>Q 7
It is often said that photosynthesis converts carbon dioxide to oxygen. Is this correct? Explain.
HARD
AS and A Level
IMPORTANT
Biology for Cambridge International AS & A Level coursebook 2nd Edition Digital Access>Chapter 13 - Photosynthesis>Questions>Q 9

In separate experiments, an actively photosynthesising plant was supplied with one of two labelled reactants:

  • water containing the 18O isotope of oxygen.
  • carbon dioxide containing the 17O isotope of oxygen.

In which products of photosynthesis would these isotopes be found?

MEDIUM
AS and A Level
IMPORTANT
Biology for Cambridge International AS & A Level coursebook 2nd Edition Digital Access>Chapter 13 - Photosynthesis>Questions>Q 10
Explain why the Calvin cycle stops running when there is no light and the TP (triose phosphate) is used up.
HARD
AS and A Level
IMPORTANT
Biology for Cambridge International AS & A Level coursebook 2nd Edition Digital Access>Chapter 13 - Photosynthesis>Questions>Q 11

The following graph shows the effect on the levels of GP (glycerate 3-phosphate) and TP (triose phosphate) in a chloroplast when it is exposed to light, dark and then light again. Describe and explain these results.

MEDIUM
AS and A Level
IMPORTANT
Biology for Cambridge International AS & A Level coursebook 2nd Edition Digital Access>Chapter 13 - Photosynthesis>Questions>Q 13
Which stage of the photosynthesis is limited by light intensity? Explain.