The number of DNA in chromosomes in G2 state of cell cycle is

Options

A. One
B. Two
C. Four
D. Eight

Answer

To determine the number of DNA molecules in chromosomes during the G2 phase of the cell cycle, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Cell Cycle**: The cell cycle consists of several phases: G1 (first gap), S (synthesis), G2 (second gap), and M (mitosis). Each phase has a specific role in cell growth and division.

**Hint**: Remember that the cell cycle is a series of events leading to cell division.

2. **Identify the S Phase**: During the S phase, DNA replication occurs. This means that each chromosome is duplicated, resulting in two identical sister chromatids for each chromosome.

**Hint**: Focus on what happens during the S phase; this is crucial for understanding G2.

3. **Transition to G2 Phase**: After the S phase, the cell enters the G2 phase. At this stage, the cell has completed DNA replication, and each chromosome consists of two sister chromatids.

**Hint**: Think about how many copies of DNA each chromosome has after replication.

4. **Count the DNA Molecules**: In the G2 phase, since each chromosome has been duplicated, the number of DNA molecules in each chromosome is 2. Therefore, if we consider the total number of chromosomes, the number of DNA molecules will be equal to the number of chromosomes multiplied by 2.

**Hint**: Remember that the number of chromosomes remains the same, but the amount of DNA doubles.

5. **Conclusion**: If we assume there are 2 chromosomes (as a simple example), then in the G2 phase, the total number of DNA molecules would be 2 chromosomes x 2 DNA molecules per chromosome = 4 DNA molecules. However, if the question is asking for the number of DNA molecules in one chromosome, the answer is 2.

**Hint**: Clarify whether the question is asking for the total number of DNA molecules or the number per chromosome.

### Final Answer:
The number of DNA molecules in each chromosome during the G2 phase of the cell cycle is **2**.