Production of a human protein in bacteria by genetic engineering is possible because

Options

A. bacterial cell can carry out the RNA splicing reactions
B. the human chromosome can replicate in bacterial cell
C. the mechanism of gene regulation is identical in humans and bacteria
D. the genetic code is universal

Answer

To answer the question regarding the production of a human protein in bacteria through genetic engineering, let's analyze the options provided step by step.

### Step-by-Step Solution:

1. **Understanding Genetic Engineering**: Genetic engineering involves manipulating an organism's DNA to produce desired traits or products. In this case, we are looking at producing human proteins in bacteria.

2. **Evaluating the Options**:
- **Option A**: "Bacterial cell can carry out the RNA splicing reaction."
- This is incorrect. RNA splicing is a process that occurs in eukaryotic cells, not in prokaryotic cells like bacteria.

- **Option B**: "The human chromosome can replicate in bacterial cell."
- This is also incorrect. Bacteria do not have the machinery to replicate human chromosomes. They can replicate small fragments of DNA (genes) using vectors, but not entire chromosomes.

- **Option C**: "The mechanism of gene regulation is identical in humans and bacteria."
- This statement is false. The mechanisms of gene regulation differ significantly between prokaryotes (like bacteria) and eukaryotes (like humans). Bacterial gene regulation is simpler.

- **Option D**: "The genetic code is universal."
- This is correct. The genetic code is indeed universal, meaning that the same codons (three-nucleotide sequences) code for the same amino acids across different organisms, including bacteria and humans.

3. **Conclusion**: The correct answer is that the production of a human protein in bacteria by genetic engineering is possible because the genetic code is universal. This allows the bacteria to translate human genes into proteins effectively.

### Final Answer:
The production of a human protein in bacteria by genetic engineering is possible because **the genetic code is universal**.

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