Question

Which of the following are NOT considered as the part of endomembrane system?

1. Mitochondria
2. Endoplasmic reticulum
3. Chloroplasts
4. Golgi complex
5. Peroxisomes

Choose the most appropriate answer from the options given below:

• A. A, C and E only
• B. A and D only
• C. A, D and E only
• D. B and D only

Answer 1

The Correct Option is A

The endomembrane system in eukaryotic cells consists of different membranes that are either physically connected or communicate with each other through the transport of small vesicles. It includes structures such as the endoplasmic reticulum, Golgi complex, lysosomes, and vesicles involved in transport and storage.

Let's evaluate each of the options provided as candidates that are not part of the endomembrane system:

1. Mitochondria: They are not part of the endomembrane system. Mitochondria have their own membranes and are involved primarily in energy conversion processes within the cell.
2. Endoplasmic reticulum: This is a key component of the endomembrane system, involved in synthesis and transport of proteins and lipids.
3. Chloroplasts: Similar to mitochondria, chloroplasts have their own membranes and are not considered part of the endomembrane system. They are involved in photosynthesis in plant cells.
4. Golgi complex: It is an integral part of the endomembrane system, functioning in modifying, sorting, and packaging of proteins and lipids for secretion or delivery to other organelles.
5. Peroxisomes: Although they are involved in the breakdown of fatty acids and detoxification, peroxisomes are not part of the endomembrane system as they do not engage in the vesicular transport associated with this system.

From the above analysis, the structures that are NOT part of the endomembrane system are:

• Mitochondria
• Chloroplasts
• Peroxisomes

Hence, the most appropriate answer is: A, C and E only

Answer 2

(A) Mitochondria are not considered part of the endomembrane system. They are double-membrane organelles involved in energy production through cellular respiration.
(C) Chloroplasts  are not part of the endomembrane system. They are organelles found in plant cells that are responsible for photosynthesis. 
(E) Peroxisomes are not part of the endomembrane system. They are single-membrane organelles involved in various metabolic processes, including the breakdown of fatty acids and detoxification.

Endoplasmic Reticulum (B) and Golgi complex (D) are indeed part of the endomembrane system, involved in protein synthesis, modification, and transport within the cell.

The correct option is (A): A, C and E only