Recombinant protein is :

Options

A. Prepared by ligating amino acid sequence of different sources
B. Replication of any protein encoding gene in a heterolgous host
C. Repliciaton of a protein encoding gene in a homologus host
D. A protein encoding gene expressed in a heterologous host

Answer

### Step-by-Step Solution:

1. **Definition of Recombinant Protein**:
- A recombinant protein is a protein that is encoded by recombinant DNA. This means that the DNA has been altered to include genes from different sources.

2. **Formation of Recombinant DNA**:
- Recombinant DNA is created when DNA from two different organisms is combined. For example, a gene from Organism A is inserted into the DNA of Organism B.

3. **Transcription and Translation**:
- Once the recombinant DNA is established, it undergoes transcription (where the DNA is copied into mRNA) and then translation (where the mRNA is used to synthesize the protein).

4. **Identifying the Correct Option**:
- To determine which option correctly describes recombinant protein, we need to look for a statement that indicates it is derived from recombinant DNA.
- The first option suggests that recombinant protein is prepared by combining amino acid sequences from different sources, which is incorrect.
- The second option talks about replicating a protein-encoding gene in a heterologous host, which aligns with the definition of recombinant protein since it involves expressing a gene from one organism in another.

5. **Conclusion**:
- The correct answer is the option that states recombinant protein is formed by the replication of a protein-encoding gene in a heterologous host.