How many chromosomes shall be present in a diploid cell at mitotic anaphase if its egg cell has 10 chromosomes?

Answer

To solve the problem of how many chromosomes are present in a diploid cell at mitotic anaphase when its egg cell has 10 chromosomes, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Chromosome Number in the Egg Cell**:
- The problem states that the egg cell has 10 chromosomes. Egg cells are haploid (n), meaning they contain half the number of chromosomes compared to diploid cells.

2. **Determine the Diploid Chromosome Number**:
- Since the egg cell is haploid and has 10 chromosomes, we can calculate the diploid number (2n) by doubling the haploid number.
- Diploid number (2n) = 2 × haploid number (n) = 2 × 10 = 20 chromosomes.

3. **Understand the Cell Cycle and Mitosis**:
- In a diploid cell undergoing mitosis, the chromosome number remains constant throughout the stages of mitosis until the telophase.
- During the anaphase stage of mitosis, the sister chromatids are pulled apart, but the total number of chromosomes (considering each chromatid as a separate chromosome) is still counted.

4. **Count the Chromosomes at Anaphase**:
- At anaphase, the diploid cell will have replicated its DNA during the S phase of the cell cycle. Thus, while there are 20 chromosomes, each has been duplicated, resulting in 40 chromatids.
- Therefore, at anaphase, the diploid cell will have 40 chromosomes (counting each chromatid separately).

5. **Final Answer**:
- The total number of chromosomes present in the diploid cell at mitotic anaphase is 40.

### Summary:
- The diploid cell at mitotic anaphase will have **40 chromosomes**.