The function of mRNA is to :

Options

A. provide specific binding sites for a series of specific t-RNA molecules
B. hold a group of ribosomes together
C. transfer the genetic code to ribosomal RNA
D. transfer the genetic code to DNA

Explanation

To answer the question about the function of mRNA, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding mRNA**: mRNA stands for messenger RNA. It is a type of RNA that carries genetic information from DNA to the ribosome, where proteins are synthesized.

2. **Central Dogma of Molecular Biology**: The central dogma describes the flow of genetic information. It states that DNA is transcribed into mRNA, and then mRNA is translated into proteins. This process is unidirectional.

3. **Transcription Process**: The first step in the central dogma is transcription, where the DNA sequence is copied into mRNA. This mRNA then carries the genetic code necessary for protein synthesis.

4. **Translation Process**: The second step is translation, where the mRNA is read by ribosomes to synthesize proteins. The ribosome reads the sequence of codons (three-nucleotide sequences) on the mRNA.

5. **Role of tRNA**: Transfer RNA (tRNA) molecules bring the appropriate amino acids to the ribosome. Each tRNA has an anticodon that is complementary to the codon on the mRNA.

6. **Binding Sites in Ribosome**: The ribosome has specific sites (A, P, and E sites) where tRNA can bind. The mRNA provides the specific binding sites for the tRNA, allowing for the correct sequence of amino acids to be assembled into a protein.

7. **Peptide Bond Formation**: As the tRNA molecules bring amino acids to the ribosome, peptide bonds form between the amino acids, creating a polypeptide chain, which eventually folds into a functional protein.

### Conclusion:
The primary function of mRNA is to provide the specific binding sites for tRNA molecules, facilitating the transfer of genetic information from DNA to proteins during the process of translation.

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