NEETBotanyPhotosynthesis in Higher Plants
Why is the Z scheme called so?
Options
- ABecause it forms a zigzag pattern
- BBecause it is discovered by a scientist named Z
- CBecause it forms a Z shape when carriers are placed in a sequence on a redox potential scale
- DBecause it occurs at night
Correct answer
C. Because it forms a Z shape when carriers are placed in a sequence on a redox potential scale
Step-by-step solution
The movement of electrons is downhill, in terms of an oxidation-reduction or redox potential scale. The electrons are not used up as they pass through the electron transport chain, but are passed on to the pigments of photosystem PS I. Simultaneously, electrons in the reaction centre of PS I are also excited when they receive red light of wavelength 700 nm and are transferred to another accepter molecule that has a greater redox potential. These electrons then are moved downhill again, this time to a molecule of en