Glycolysis takes place in :

Options

A. eukaryotic cells only
B. cyanobacteria only
C. anaerobic bacteria
D. virtually all cells

Explanation

**Step-by-Step Solution:**

1. **Understanding Glycolysis**: Glycolysis is the first step of cellular respiration where glucose is broken down to extract energy. This process is essential for the energy needs of the cell.

2. **Location of Glycolysis**: Glycolysis occurs in the cytoplasm of the cell. This is important because it indicates that the process is not restricted to any specific type of cell organelle.

3. **Anaerobic Nature of Glycolysis**: Glycolysis is an anaerobic process, meaning it does not require oxygen to occur. This allows it to take place in various environments, including those that lack oxygen.

4. **Occurrence in Organisms**: Glycolysis is a universal process that occurs in virtually all living organisms, including eukaryotic cells, prokaryotic cells (like bacteria), and even in anaerobic bacteria.

5. **Conclusion**: Based on the information gathered, the correct answer to the question "Glycolysis takes place in:" is "virtually all cells."

**Final Answer**: Glycolysis takes place in virtually all cells.

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