The plasmalemma of the cell is a

Options

A. fully permeable membrane
B. selectively permeable membrane
C. semipermeable membrane
D. impermeable membrane

Answer

### Step-by-Step Solution

1. **Understanding the Term "Plasmalemma":**
- The term "plasmalemma" refers to the plasma membrane of a cell. It is essential to recognize that this term is often used interchangeably with "plasma membrane."

2. **Defining the Plasma Membrane:**
- The plasma membrane is a biological membrane that separates and protects the interior of the cell from the external environment. It plays a crucial role in maintaining the cell's integrity.

3. **Characteristics of the Plasma Membrane:**
- The plasma membrane is described as a **selectively permeable membrane**. This means that it allows certain substances to pass through while blocking others.

4. **Function of Selective Permeability:**
- Selective permeability is vital for the cell's function as it regulates the movement of ions, nutrients, and waste products in and out of the cell. This control is crucial for maintaining homeostasis within the cell.

5. **Distinguishing Between Types of Membranes:**
- It is important to differentiate between various types of membranes:
- **Fully Permeable Membrane:** Allows all substances to pass through. This is incorrect for the plasma membrane.
- **Semi-Permeable Membrane:** Allows certain substances to pass based on size. This is not entirely accurate for the plasma membrane since it also considers the nature of the molecules.
- **Impermeable Membrane:** Does not allow any substances to pass through. This is also incorrect for the plasma membrane.

6. **Conclusion:**
- Based on the definitions and characteristics discussed, the correct answer to the question "The plasmalemma of the cell is a" is that it is a **selectively permeable membrane**.

### Final Answer:
The plasmalemma of the cell is a **selectively permeable membrane**.

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