Question

Which animal cell structure is characterized by selective permeability?

• A. Chromosome
• B. Cell membrane
• C. Cell wall
• D. Ribosomes

Answer 1

The correct option is B

Cell membrane

The correct option is B

Explanation of the correct option:

1. The plasma membrane or cell membrane is the outermost layer in the animal cell and the second outermost layer in the plant cell.
2. Functions as a physical barrier between the external environment and the inner cell environment.
3. It is a selectively permeable membrane, which permits the movement of only certain molecules both in and out of the cell.

Explanation of the incorrect option:

Option A:

1. Chromosomes are thread-like structures and present in the nucleus of the cell.
2. They are composed of DNA and protein.
3. They contain genetic material.
4. They are visible during cell division.

Option C:

1. The cell wall is mainly composed of cellulose.
2. Cellulose is a polysaccharide type of carbohydrate consisting of several hundred to many thousands of units of glucose.
3. Around 6000 molecules of glucose contribute to preparing cellulose.
4. Cellulose is an important structural component of the primary cell wall of green plants and many forms of algae.

Option D:

1. Ribosomes are the only cell organelle present in this cell that is not membrane-bound.
2. Ribosomes are produced by nucleolus.

Final answer: Animal cell structure characterized by selective permeability is the cell membrane.