Question

The proteins and lipids, essential for building the cell membrane, are manufactured by

• A. Endoplasmic reticulum
• B. Golgi apparatus
• C. Plasma membrane
• D. Mitochondria

Answer 1

The correct option is A

Endoplasmic reticulum

The correct option is A:

Explanation of the correct option:

1. Endoplasmic reticulum consists of membrane bound channels, tubules, sacs or vesicles. Two types of Rough E.R and Smooth E.R.
2. Rough E.R. - presence of ribosomes on its surface. It is the location of protein synthesis.
3. Smooth E.R. — is devoid of ribosomes, help in lipid synthesis.
4. Other functions include- Intracellular and intercellular transport of substances, acts as an internal support for cytoplasm. It is the site of biochemical activities, detoxify poisons

Explanation of the incorrect options:

Golgi apparatus

1. Golgi apparatus are membrane bound cell organelle with sacs, tubules, vesicles which helps to secrete biochemical compounds.
2. It have thin and curved structures called cisternae. In plants it is called dictyosomes.
3. The main functions are repair and synthesis of cell membrane, cell wall.
4. Lysosome are formed from Golgi apparatus.
5. Another important function is storage, modification and packaging of biochemical compounds

Mitochondria

1. Are rod shaped organelle seen in eukaryotic cell which is known as the power house of the cell.
2. This organelle is known as the power house of the cell as it contains enzyme necessary for the oxidation of food and also for generating ATP.
3. ATP is known as the energy currency of the cell as it provide energy for new chemical compound formation and mechanical work.
4. Mitochondria is bound by two membrane structures called outer membrane and inner membrane.
5. Outer membrane is smooth and has many pores in them.
6. Inner membrane is highly folded to form structures called cristae, which increases the surface area for ATP synthesis.
7. Mitochondrial matrix contain DNA, ribosomes and enzymes which take part in protein synthesis and respiration respectively.

Plasma membrane

1. Is the outer most layer that separates outer environment from inside of the cell.
2. It includes protoplasm which contains cytoplasm and nucleus
3. Is a selectively permeable membrane
4. It is composed of lipids and proteins.
5. Main functions include mechanical barrier, cell continuity, osmosis, endocytosis etc.

Thus, the proteins and lipids, essential for building the cell membrane, are manufactured by endoplasmic reticulum.