Question

Quantasomes are found in ___
a. Mitochondria
b. Chloroplast
c. Lysosome
d. Endoplasmic reticulum

Answer 1

Quantasomes are the main sites of photosynthesis reactions to occur and are composed of proteins, lipids, and photosynthetic pigments. They are composed of lipids and proteins which contain various photosynthetic pigments and redox carriers.

Complete answer:
Quantasomes are sites of photosynthetic reactions present in the thylakoid membrane of the chloroplast. They are embedded in a paracrystalline array along the surface of the thylakoid disks. They are composed of lipids and proteins which contain various photosynthetic pigments and redox carriers.
They occur in two sizes-
- The smaller quantasomes are thought to represent sites of photosystem I.
- The larger quantasomes represent photosystem II.
From the above options:
• Mitochondria is the site of energy production in the cell and no photosynthetic reaction occurs there. Therefore, option (a) is incorrect.
• Lysosomes are the suicide bags that store hydrolyzing enzymes. Therefore, option (c) is also incorrect.
• The endoplasmic reticulum is responsible for mRNA transport from the nucleus to the cytosol. Therefore, option (d) is incorrect.
• Thus the quantasomes are present in the thylakoid membrane which is a part of the chloroplast.
Hence, the correct answer is option (B).

Additional information:
The function of the chloroplast is
• They convert light energy into chemical energy.
• They help in providing various metabolic activities for plant cells- synthesis of membranes of lipids, fatty acids, etc.

Note: The above-mentioned cell organelles are present in both animals and plants, except chloroplast which is only present in plants. Quantasomes are sites of photosynthesis which also occurs in plants. Therefore, this is another way to get to the answer, where even if the functions of the individual organelles are unknown still the answer can be derived.