At the end of the G2 phase, the amount of DNA in a diploid cell having the amount of chromosome 2C will be

Options

A. C.
B. 2C.
C. 4C.
D. `C//2.`

Answer

To solve the question regarding the amount of DNA in a diploid cell at the end of the G2 phase with an initial amount of DNA represented as 2C, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Phases of the Cell Cycle**:
- The cell cycle consists of several phases: G1, S, G2, and M (mitosis).
- G1 phase is the first gap phase where the cell grows and prepares for DNA replication.
- The S phase is where DNA replication occurs, leading to the duplication of the genetic material.
- G2 phase is the second gap phase where the cell continues to grow and prepares for mitosis.

2. **Identifying the Amount of DNA**:
- The question states that at the end of the G2 phase, the amount of DNA in the cell is represented as 2C.
- Here, "C" refers to the amount of DNA in a haploid set of chromosomes. Therefore, 2C indicates that the cell is diploid, meaning it has two sets of chromosomes.

3. **DNA Replication in the S Phase**:
- During the S phase, the DNA is replicated. This means that the amount of DNA in the cell doubles.
- If the amount of DNA was 2C before the S phase, after replication during the S phase, it will become 4C.

4. **Amount of DNA at the End of G2 Phase**:
- At the end of the G2 phase, the DNA has been replicated, and thus the amount of DNA in the diploid cell will be 4C.
- It is important to note that while the amount of DNA has doubled, the number of chromosomes remains the same until mitosis occurs.

5. **Conclusion**:
- Therefore, at the end of the G2 phase, the amount of DNA in the diploid cell will be 4C.

### Final Answer:
The amount of DNA in a diploid cell at the end of the G2 phase is **4C**.