Question

Movement of substances in and out of the cell is controlled by

• A. Cytoplasm
• B. Cell wall
• C. Plasma membrane
• D. Nuclear membrane

Answer 1

The correct option is C

Plasma membrane

The correct option is C
Explanation of the correct option:

1. The plasma membrane is also referred to as the cell membrane.
2. All cells are bound by a cell membrane that encloses the living protoplasm consisting of cytoplasm and nucleus.
3. It provides shape and protection to the cell.
4. This thin membrane is porous and selectively permeable in nature.
5. Being selectively permeable, the plasma membrane only allows some substances to pass through it but not others.
6. This is how the plasma membrane regulates the movement of substances in and out of a cell.

Explanation of the incorrect option:
Option A:

1. The cytoplasm is a part of the protoplasm.
2. It is the translucent and jelly-like material of a cell that contains all the material inside the cell and outside of the nucleus.
3. It includes cell organelles like ribosomes, Golgi complex, vacuoles, etc.

Option B:

1. Plant cells have an additional protective covering outside the cell membrane called the cell wall.
2. A cell wall is a rigid and tough layer that provides structural support and protection to the plant.

Option D:

1. The nucleus is a membrane-bound organelle consisting of genetic materials like chromatin fibers, a jelly-like nucleoplasm, and a double-layered nuclear membrane to enclose the nucleus.
2. The nuclear membrane separates the nucleus from the cytoplasm.

Final answer: The movement of substances in and out of the cell is controlled by the plasma membrane.