Secretory vesicles are pinched off as zymogen granules from ____ side of dictyosomes.

Options

A. convex
B. concave
C. plain
D. all sides

Answer

To solve the question "Secretory vesicles are pinched off as zymogen granules from ____ side of dictyosomes," we need to understand the structure and function of dictyosomes, also known as the Golgi apparatus.

### Step-by-Step Solution:

1. **Understanding Dictyosomes**:
- Dictyosomes, or Golgi apparatus, are organelles involved in modifying, sorting, and packaging proteins and lipids for secretion or delivery to other organelles.

2. **Structure of the Golgi Apparatus**:
- The Golgi apparatus consists of flattened membrane-bound sacs called cisternae. It has two distinct faces: the convex (forming) face and the concave (maturing) face.

3. **Function of Each Face**:
- The **convex face** (cis face) is where vesicles from the endoplasmic reticulum (ER) fuse with the Golgi apparatus. This is where the incoming materials are received.
- The **concave face** (trans face) is where the processed materials are packaged into secretory vesicles, such as zymogen granules, which are then pinched off and sent to their destination.

4. **Identifying the Correct Answer**:
- Since the question asks from which side secretory vesicles (zymogen granules) are pinched off, we focus on the maturing phase of the Golgi apparatus.
- The zymogen granules are released from the **concave face** of the dictyosome.

5. **Conclusion**:
- The correct answer to the question is **B. Concave**.

### Final Answer:
Secretory vesicles are pinched off as zymogen granules from the **concave side** of dictyosomes.