The process that takes place in the dark stage of photosynthesis is…
JAMB Biology Tutorial on Respiration Process, Types, Mechanism, Functions and Past Questions
The process that takes place in the dark stage of photosynthesis is
A. oxidation of water
B. photolysis of water
C. oxidation of carbon (IV) oxide
D. reduction of carbon (IV) oxide
Photosynthesis generally involves two stages of reactions, the light and dark reactions. The light reaction involves the use of sunlight to split water and produce energy in form of ATP; the dark reactions uses the ATP produce to carry out its processes.
However, in terms of electron transfer, photosynthesis generally involves the oxidation or removal of electrons from water molecules in presence of light, and the reduction or gaining of these electrons by carbon dioxide in the dark.
Now for the right answer to the above question:
- Oxidation of water occurs in the presence of light. so, A is quite incorrect.
- Option B is same as option A, oxidation of water is same as photolysis of water. B is also incorrect.
- Oxidation of carbon dioxide would imply removal of electrons from it, this is clearly not the case. So, C is incorrect.
- D is correct, carbon dioxide gained electrons, and reduction involves the gain of electron(s)
You may please note that:
- The gain and lose of electrons narrative is an over simplification of what really occurred, actual analysis of this process is much more complex.
Use the questions and answers session to raise further questions on this topic…
/ culled from 2017 JAMB-UTME biology question 14 /