Question

Which of the following is a correct feature of photosystems?

• A. $P_{700}$is the reaction centre of PS II
  
• B. PS I is a pheophytin-quinone type reaction centre
• C. Last electron acceptor is Plastoquinone in PS II
• D. Photolysis is associated with PS II

Answer 1

The correct option is D Photolysis is associated with PS II

Photosynthesis has two stages:
Light reaction and dark reaction.

Light reaction can be of two types:
Non-cyclic photophosphorylation and cyclic photophosphorylation.

In non-cyclic photophosporylation, there are two photosystems. PS II is followed by PS I.

• $P_{680}$ is the reaction centre of PS II. PS II is also known as a pheophytin-quinone type reaction centre. Splitting of water is associated with PS II. This electron is given to $P_{680}^{+}$. Plastoquinone is the last electron acceptor in PS II. Plastocyanin transfers electrons between cytochrome $b_{6}f$ and $P_{700}^{+}$.
• $P_{700}$ is the reaction centre of PS I. PS I is also known as Fe-S type reaction centre. The last electron acceptor in PS I is ferredoxin.