Question

The site of dark reaction of photosynthesis is

• A. granum
• B. stroma
• C. duodenum
• D. large intestine

Answer 1

The correct option is B

stroma

The correct option is (B):
Explanation for the correct option:

Stroma:

1. Dark reactions occur in the stroma.
2. The dark reaction takes place in the stroma of the chloroplast, where the light reaction's products are used.
3. Sugar molecules are generated from carbon dioxide and water molecules in a light-independent process.
4. RuBisCo helps in CO₂ fixation to form the glucose in the dark reaction.

Explanation for the incorrect option:
Option (A):

Granum:

1. Light reactions occur in the granum.
2. Chlorophyll absorbs the light in the form of packets called photons.
3. Chlorophyll gets excited and energy is released which is utilized in the formation of energy molecules like ATP.

Option (C):

Duodenum:

Duodenum is the first part of the small intestine in humans and is not related with photosynthesis.

Option (D):

Large intestine:

Large intestine is the part of the digestive system in humans which ends in anus and is not related with photosynthesis.

Final Answer: The site of dark reaction of photosynthesis is stroma.