In an eukaryotic cell, glycolysis takes place :

Options

A. in the cytoplasm
B. within mitochondrion
C. on rough ER
D. within grana

Explanation

### Step-by-Step Solution:

1. **Understanding Glycolysis**: Glycolysis is the metabolic pathway that converts glucose into pyruvate, producing ATP and NADH in the process. It is a crucial step in cellular respiration.

2. **Identifying the Location**: In eukaryotic cells, glycolysis occurs in the cytoplasm. This is where the enzymes necessary for the glycolytic pathway are located.

3. **Evaluating Other Options**:
- **Mitochondrion**: While mitochondria are essential for aerobic respiration and ATP production, glycolysis does not occur here. Instead, it occurs in the cytoplasm before the products enter the mitochondria for further processing.
- **Rough Endoplasmic Reticulum (RER)**: The RER is primarily involved in protein synthesis, not in glycolysis.
- **Within Granule**: Granules are part of chloroplasts involved in photosynthesis, not glycolysis.

4. **Conclusion**: Since glycolysis occurs in the cytoplasm of eukaryotic cells, the correct answer is that glycolysis takes place in the cytoplasm.

### Final Answer:
In an eukaryotic cell, glycolysis takes place in the **cytoplasm**.

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