Question

All of the following are correct descriptions of photosynthesis except:

A) The Calvin Cycle is endergonic.
B) Electrons are supplied to the reaction center via the splitting of water, which yields O2 as a byproduct
C) Chlorophyll and accessory pigments capture energy from the sun in the form of electrons, which they use to drive the electron transport chains of photosystems I and II.
D) ATP and NADPH generated in the light-dependent reactions are used to power CO2 fixation via the Calvin cycle in the light-independent reactions.

Answer 1

The correct answer will be option- C.

Step-by-step explanation:

Photosynthesis is a complex process which synthesizes the glucose molecules by converting sunlight energy into chemical energy. Photosynthesis proceeds in two phases: light-dependent and light-independent reaction.

The light-dependent reactions take place in the thylakoid membrane where the photo-system chlorophyll absorbs the sunlight photons which excites the electrons of the chlorophyll.

Chlorophyll transfers the electron to antenna molecules and finally to reaction center form where it enters the electron transport chain.

This creates instability which causes the photolysis of water molecules and release of oxygen as a byproduct. The light reaction produces intermediates like ATP and NADPH which are utilized during the Calvin cycle.

Thus, Option-C is the correct answer.

Answer 2

The correct answer is option C.

Step-by-step explanation:

The chlorophyll and the accessory pigments captivate energy from the Sun in the form of light. This energy is used to dissociate water known as photolysis to generate electrons, protons, and oxygen.

The oxygen is produced as a by-product of the process, while the electrons are provided to the reaction centers, and the protons are further used in the process of building up of proton gradient.