Q. Which of the following statements is true with regard to the light reaction of photosynthesis?
A) In PS-II the reaction centre chlorophyll-$\alpha$ has an absorption peak at 700 nm hence, is called $P_{700}$
B) In PS-I the reaction centre chlorophyll-$\alpha$ has an absorption maxima at 680 nm and is called $P_{680}$
C) The spitting of water molecule is associated with PS-I
D) Photosynthems-I and II are involved in Z scheme
Explanation
Photophosphorylation is the synthesis of ATP from ADP and inorganic phosphate in the presence of sun-light. When the two photosystems work in series, first PS-II and then the PS-I, a process called non-cyclic Photophosphorylation occurs. The two photosystems are connected through an electron transport chain in the Z-scheme (due to the shape of path of electrons flow). Both ATP and NADH+$H^{+}$ are synthesized by this kind of electron flow.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.