Question

In photosynthesis what occurs in PS - II?

• A. It takes longer wavelength of light and $e^{-}$ from $H_{2}O$
• B. It takes shorter wavelength of light and $e^{-}$from $H_{2}O$
• C. It takes longer wavelength of light and $e^{-}$ from NADP
• D. It takes shorter wavelength of light and $e^{-}$ from NADP

Answer 1

Answer: (B)

. Green plants and algae use two type of photo-system called PS-I and PS -II. In PS-I chlorophyll absorb maximum at $700nm$ wavelength of light thus reaction centre is $P_{700}$ and PS-II absorb maximum $680nm$ wavelength of light thus reaction centre is $P_{680}\cdot P_{680}$ (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.