The correct option is (a).
Explanation
A typical cell consists of three fundamental components: the cell membrane, the cytoplasm, and the nucleus. Each component possesses distinct structural properties and functions vital for cellular life.- Statement 1 is Correct: The cell membrane (also known as the plasma membrane) is the boundary that encloses the cell, separating it from the external environment. It is porous and selectively permeable, meaning it regulates the movement of substances into and out of the cell.
- Statement 2 is Incorrect: The nucleus is a distinct, usually spherical organelle that functions as the control center of the cell. It is not the jelly-like substance filling the cell. The jelly-like substance located between the cell membrane and the nucleus is called the cytoplasm.
- Statement 3 is Incorrect: Cytoplasm is the fluid medium within the cell membrane containing various organelles. The hard, rigid outer covering found specifically in plant cells (external to the cell membrane) is the cell wall, which provides protection and structure.
Key Takeaway: The cell membrane acts as a selective barrier, the cytoplasm is the internal fluid medium, and the nucleus serves as the central regulatory organelle. The cell wall is a rigid protective layer found in plant cells, distinct from the cytoplasm.