Prokaryotes are primitive cells. They lack an organized nucleus and other membrane-bound organelles. Which of the following structures is not found in prokaryotic cells?

Options

A. Cell membrane
B. Mitochondrion
C. Chromosome
D. Cytoplasm

Answer

**Step-by-Step Solution:**

1. **Understanding Prokaryotic Cells**: Prokaryotic cells are simple, primitive cells that do not have a well-defined nucleus or membrane-bound organelles. This is a key characteristic that distinguishes them from eukaryotic cells.

2. **Identifying Structures**: We need to analyze the options provided in the question to determine which structure is not found in prokaryotic cells.

3. **Option Analysis**:
- **Cell Membrane**: Prokaryotic cells do have a cell membrane. It is selectively permeable, allowing certain substances to enter and exit the cell.
- **Mitochondria**: Mitochondria are membrane-bound organelles responsible for energy production through cellular respiration. Prokaryotic cells do not have mitochondria as they lack membrane-bound organelles.
- **Chromosome**: Prokaryotic cells contain chromosomes, which carry genetic material. However, their chromosomes are typically circular and not enclosed within a nucleus.
- **Cytoplasm**: Prokaryotic cells contain cytoplasm, which is the gel-like substance where cellular processes occur.

4. **Conclusion**: Based on the analysis, the structure that is not found in prokaryotic cells is **mitochondria**. Therefore, the correct answer is the option that refers to mitochondria.

**Final Answer**: Mitochondria are not found in prokaryotic cells.

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