Prokaryotes can be distinguished from eukaryotes as they lack

Options

A. RNA
B. Ribosomes
C. Gene discontinuity
D. Unique DNA sequence

Answer

### Step-by-Step Solution:

1. **Understanding Prokaryotes and Eukaryotes**:
- Prokaryotes are single-celled organisms that lack a defined nucleus and membrane-bound organelles. Examples include bacteria and archaea.
- Eukaryotes, on the other hand, have a defined nucleus and various membrane-bound organelles.

2. **Identifying the Key Difference**:
- The primary distinguishing feature of prokaryotes is the absence of a nuclear envelope. This means that their genetic material is not enclosed within a membrane-bound nucleus.

3. **Transcription Process**:
- In prokaryotes, transcription occurs in the cytoplasm, and the RNA produced is immediately ready for translation without any modifications. This RNA is referred to as mature RNA.
- In contrast, eukaryotes undergo a more complex process where the initial RNA transcript (primary transcript) contains both introns (non-coding regions) and exons (coding regions).

4. **RNA Processing in Eukaryotes**:
- Eukaryotic RNA undergoes several modifications, including splicing (removal of introns), capping, and polyadenylation (adding a tail), to produce mature mRNA that can be translated into proteins.

5. **Conclusion**:
- The key distinction is that prokaryotes lack a defined nucleus and the complex RNA processing mechanisms found in eukaryotes. Therefore, the correct answer is that prokaryotes can be distinguished from eukaryotes as they lack a nuclear envelope and the associated gene discontinuity.

### Final Answer:
Prokaryotes can be distinguished from eukaryotes as they lack a nuclear envelope and the complex RNA processing mechanisms (gene discontinuity).

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