In 1980, F. Sanger was awarded Nobel prize second time to be shared by Gilbert and Maxum for their work on

Options

A. Genetic mapping of chromosomes
B. Determining amino acid sequence of insulin
C. Determining base sequence of DNA of virus
D. Determining the structure of DNA

Explanation

**Step-by-Step Text Solution:**

1. **Identify the Key Contributors**: In 1980, Frederick Sanger was awarded the Nobel Prize, which he shared with Gilbert and Maxam. Their work was pivotal in the field of molecular biology.

2. **Understand the Nature of Their Work**: The primary focus of Sanger, Gilbert, and Maxam's work was on DNA sequencing, specifically the methods they developed to determine the nucleotide sequences of DNA.

3. **Recognize the Significance of DNA Sequencing**: DNA sequencing is crucial because it reveals the order of nucleotides in a DNA molecule. This sequence is essential for understanding genetic information and how it translates into proteins.

4. **Describe the Methods Used**: Sanger developed the chain termination method for DNA sequencing. This method involves synthesizing DNA strands and using dideoxynucleotides (ddNTPs) that terminate the chain at specific bases, allowing for the determination of the sequence.

5. **Explain the Process**: In the chain termination method, a single-stranded DNA template is used along with a primer and both normal nucleotides and ddNTPs. As DNA polymerase extends the chain, the incorporation of a ddNTP stops further extension, resulting in fragments of varying lengths that can be analyzed to deduce the sequence.

6. **Highlight the Impact of Their Work**: The work of Sanger, Gilbert, and Maxam laid the foundation for modern genetic research, enabling scientists to sequence DNA from various organisms, including viruses, which has vast implications in genetics, medicine, and biotechnology.

**Final Answer**: In 1980, F. Sanger was awarded the Nobel Prize, which he shared with Gilbert and Maxam for their work on determining the base sequence of DNA.

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