Prokaryotes are characterised by

Options

A. Absence of internal compartmentalisation
B. Absence of nucleus
C. 70S ribosomes
D. All the above.

Answer

**Step-by-Step Solution:**

1. **Understanding Prokaryotes**: Prokaryotes are unicellular organisms that lack a well-defined nucleus. This is a fundamental characteristic that distinguishes them from eukaryotes.

2. **Absence of Nucleus**: In prokaryotes, the genetic material is not enclosed within a nuclear membrane. Instead, it is found in a region called the nucleoid. This absence of a true nucleus is a key feature of prokaryotic cells.

3. **Lack of Internal Compartmentalization**: Prokaryotic cells do not possess membrane-bound organelles, which means they lack internal compartmentalization. This means that all cellular processes occur within the same space without the separation that organelles provide in eukaryotic cells.

4. **Ribosome Type**: Prokaryotes contain 70S ribosomes, which are composed of two subunits: 50S and 30S. This is different from eukaryotic cells, which typically have 80S ribosomes.

5. **Evaluating the Options**:
- Option A: Absence of internal compartmentalization - Correct.
- Option B: Absence of nucleus - Correct.
- Option C: 70S ribosomes - Correct.
- Option D: All of the above - Since all previous options are correct, this is the correct answer.

6. **Conclusion**: Therefore, prokaryotes are characterized by the absence of internal compartmentalization, absence of a nucleus, and the presence of 70S ribosomes. The correct answer is D: all of the above.

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