JIPMER2005BotanyPhotosynthesis in Higher Plants
In photosynthesis what occurs in PS-II?
Options
- AIt takes longer wavelength of light and e⁻ from H ₂ O
- BIt takes shorter wavelength of light and e⁻ from H ₂ O
- CIt takes longer wavelength of light and e⁻ from NADP
- DIt takes shorter wavelength of light and e⁻ from NADP
Correct answer
B. It takes shorter wavelength of light and e⁻ from H ₂ O
Step-by-step solution
Green plants and algae use two type of photo-system called PS-I and PS -II. In PS-I chlorophyll absorb maximum at 700 nm wavelength of light thus reaction centre is P ₇₀₀ and PS-II absorb maximum 680 nm wavelength of light thus reaction centre is P ₆₈₀ . P ₆₈₀ (PS-II) extracts an electron from water, returning to its unexcited state because hydrolysis of H ₂ O occurs in PS-II. So, O ₂ evolved in PS-II come from water.