which of the following cell organelle is responsible for the synthesis of steroids and lipids?

Options

A. SER
B. RER
C. Mitochondria
D. Ribosome

Answer

To answer the question "Which of the following cell organelle is responsible for the synthesis of steroids and lipids?", we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Options**: The question provides four options:
- A) Smooth Endoplasmic Reticulum (SER)
- B) Rough Endoplasmic Reticulum (RER)
- C) Mitochondria
- D) Ribosomes

2. **Understand the Function of Each Organelle**:
- **Smooth Endoplasmic Reticulum (SER)**: This organelle is involved in the synthesis and metabolism of lipids and steroid hormones. It does not have ribosomes on its surface.
- **Rough Endoplasmic Reticulum (RER)**: This organelle is studded with ribosomes and is primarily responsible for the synthesis of proteins.
- **Mitochondria**: Known as the powerhouse of the cell, mitochondria are responsible for generating ATP (energy) but are not involved in lipid or steroid synthesis.
- **Ribosomes**: These are the sites of protein synthesis and do not synthesize lipids or steroids.

3. **Analyze the Functions**: Based on the functions:
- The SER is specifically associated with lipid and steroid synthesis.
- The RER, mitochondria, and ribosomes do not play a role in the synthesis of steroids and lipids.

4. **Select the Correct Answer**: Given the analysis, the correct answer is:
- **A) Smooth Endoplasmic Reticulum (SER)**

### Final Answer:
The cell organelle responsible for the synthesis of steroids and lipids is the **Smooth Endoplasmic Reticulum (SER)**.

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