What happenes when small subunit of the ribosome encounters mRNA?

Options

A. seperationof the small and the larger subunit of the ribosome
B. Translation of the central dogma of DNA
C. joining of the small and the larger subunit of the ribosome
D. transcription of the central of DNA

Answer

### Step-by-Step Text Solution:

1. **Encounter of Small Subunit with mRNA**: When the small subunit of the ribosome encounters mRNA, it recognizes and binds to the mRNA strand. This is a crucial step in the initiation of protein synthesis.

2. **Initiation of Translation**: The binding of the small ribosomal subunit to mRNA triggers the initiation of the translation process. Translation is the process by which the genetic code carried by mRNA is used to synthesize proteins.

3. **Formation of the Ribosome Complex**: After the small subunit binds to the mRNA, the large subunit of the ribosome then associates with this complex. This formation creates a functional ribosome that is ready to translate the mRNA into a polypeptide chain.

4. **Ribosome Sites**: The large subunit contains three important sites: the A (aminoacyl) site, the P (peptidyl) site, and the E (exit) site. These sites play crucial roles in the binding of tRNA and the formation of peptide bonds between amino acids.

5. **Protein Synthesis**: As the ribosome moves along the mRNA, tRNA molecules bring amino acids to the ribosome, where they are added to the growing polypeptide chain. This process continues until a stop codon is reached, signaling the end of protein synthesis.

6. **Completion of Translation**: Once the entire mRNA has been translated, the newly synthesized protein is released from the ribosome, completing the process of translation.