If 46 chromosomes are present at `G_(1)` phase, then the number of chromosomes after S phase would be

Options

A. 23
B. 92
C. 47
D. 46

Answer

To solve the question of how many chromosomes are present after the S phase if there are 46 chromosomes at the G1 phase, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Cell Cycle**: The cell cycle consists of several phases: G1 (Gap 1), S (Synthesis), G2 (Gap 2), and M (Mitosis). Each phase has specific functions related to cell growth and division.

2. **Identify the G1 Phase**: In the G1 phase, the cell is preparing for DNA replication. At this stage, the cell has a diploid number of chromosomes. In this case, there are 46 chromosomes.

3. **Recognize the S Phase Function**: The S phase is where DNA synthesis occurs. This means that each chromosome is replicated, resulting in two sister chromatids for each chromosome.

4. **Determine Chromosome Count After S Phase**: Although the number of chromatids doubles during the S phase (from 46 to 92 chromatids), the number of chromosomes remains the same. Therefore, after the S phase, the cell still has 46 chromosomes, but each chromosome consists of two sister chromatids.

5. **Conclusion**: Since the number of chromosomes does not change during the S phase, the answer is that there are still 46 chromosomes present after the S phase.

### Final Answer:
The number of chromosomes after the S phase would be **46**.

---