Three domains of life is based on

Options

A. Protein Sequence
B. 16S rRNA gene sequence
C. Cell wall structure
D. Mode of nutrition

Answer

To answer the question regarding the basis of the three domains of life, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding the Three Domains of Life**:
- The three domains of life are Archaea, Bacteria, and Eukarya. These domains categorize all living organisms based on fundamental differences in their cellular structure and genetic makeup.

2. **Identifying the Basis for Classification**:
- The classification into these three domains is primarily based on genetic information, specifically the sequences of ribosomal RNA (rRNA).

3. **Role of Ribosomal RNA**:
- Ribosomal RNA is a crucial component of the ribosome, which is essential for protein synthesis in all living cells. The 16S rRNA gene is particularly important for distinguishing between different species and domains.

4. **Gene Sequencing**:
- The sequencing of the 16S rRNA gene allows scientists to analyze genetic relationships among organisms. This method has provided significant insights into evolutionary biology and the classification of life forms.

5. **Conclusion**:
- Therefore, the three domains of life are based on the gene sequencing of 16S ribosomal RNA, which reflects the evolutionary relationships among organisms.

### Final Answer:
The three domains of life are based on the gene sequencing of 16S ribosomal RNA.

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