Question
Question: Grana is a part of: A. Mitochondria B. Chloroplast C. Aleurone grain D. Starch grain...
Grana is a part of:
A. Mitochondria
B. Chloroplast
C. Aleurone grain
D. Starch grain
Solution
Grana are structurally stacking of thylakoids and are found in the chloroplasts of plant cells. They are connected to each other by stroma thylakoids. The membranes of thylakoids in grana are involved in the process of photosynthesis and they contain the green photosynthetic pigments and some accessory pigments which are required for light harvesting reactions.
Complete solution:
Option A: Mitochondria are powerhouses of the cell and are involved in the process of oxidative phosphorylation to produce ATP and they have no role in the process of photosynthesis.
Option A is incorrect.
Option B: Chloroplasts are found in the cells of green plants and are involved in the process of photosynthesis. They contain grana in their double membrane structures as stacks of thylakoids.
Option B is correct.
Option C: Aleurone grains are proteins found in seeds and plant tubers. They provide nutrition to growing plants. Therefore, they are not associated with grana and photosynthesis in any way.
Option C is incorrect.
Option D: Starch grains are stored food materials in the plant cells and are not involved in the photosynthesis process. Starch grains are produced as a result of the process of photosynthesis. Grana are not part of starch grains.
Option D is also incorrect.
Hence, Option B is the correct answer.
Note:
Grana are stacks of thylakoids. Two types of thylakoids are associated with grana - the stroma thylakoids and the intergranal thylakoids. Intergranal thylakoids connect two adjacent grana. The grana are associated with an increase in light capturing efficiency of the light harvesting pigments in the thylakoid membrane by increasing the surface area of the thylakoid membrane.