An example of selectively permeable membrane is:

Options

A. plasmalemma
B. cell wall
C. chloroplast membrane
D. mitochondrial membrane

Answer

**Step-by-Step Solution:**

1. **Understanding Selectively Permeable Membrane:**
- A selectively permeable membrane is a type of biological membrane that allows certain substances to pass through while blocking others. It permits the free passage of water and selectively allows specific solute molecules to pass.

2. **Analyzing the Options:**
- The options given are:
- A) Plasma lemma
- B) Cell wall
- C) Chloroplast membrane
- D) Mitochondrial membrane

3. **Evaluating Each Option:**
- **Plasma lemma (Cell Membrane):**
- The plasma lemma, also known as the cell membrane, is made up of a lipid bilayer and is indeed selectively permeable. It allows the passage of water and certain solutes while restricting others.
- **Cell Wall:**
- The cell wall is not selectively permeable; it is rigid and allows most substances to pass freely, thus it does not fit the definition of a selectively permeable membrane.
- **Chloroplast Membrane:**
- The chloroplast membrane is not primarily recognized as selectively permeable in the same way as the plasma lemma. It has different functions and characteristics.
- **Mitochondrial Membrane:**
- The mitochondrial membrane has selective permeability, but it is not the best example when compared to the plasma lemma, which is more commonly referred to in this context.

4. **Conclusion:**
- Based on the analysis, the correct answer is **A) Plasma lemma**, as it is the best example of a selectively permeable membrane.