Cis - and trans - faces are present in

Options

A. Endoplasmic reticulum
B. Golgi body
C. Ribosomes
D. Mitochondria

Answer

To solve the question regarding the presence of cis and trans faces, let's break it down step by step:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks where cis and trans faces are present among the given options: endoplasmic reticulum, Golgi body, ribosome, and mitochondria.

2. **Identifying the Organelles**:
- **Endoplasmic Reticulum (ER)**: It is involved in protein and lipid synthesis but does not have distinct cis and trans faces.
- **Golgi Body**: This organelle is known for processing and packaging proteins and lipids. It has distinct regions known as cis and trans faces.
- **Ribosome**: This is the site of protein synthesis and does not have cis and trans faces.
- **Mitochondria**: This is the powerhouse of the cell and is involved in energy production but does not have cis and trans faces.

3. **Focusing on the Golgi Body**:
- The Golgi body has two sides:
- **Cis Face**: This is the receiving side of the Golgi apparatus, where materials enter. It is often described as the convex face.
- **Trans Face**: This is the shipping side, where materials exit. It is often described as the concave face.

4. **Conclusion**: Based on the analysis, the organelle that contains cis and trans faces is the Golgi body.

### Final Answer:
**B. Golgi body**

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