If the number of bivalents are 8 in metaphase-I, then what shall be the number of chromosomes in daughter cells after meiosis-I and meiosis-II respectively?

Answer

To determine the number of chromosomes in daughter cells after meiosis-I and meiosis-II when there are 8 bivalents in metaphase-I, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Bivalents**:
- Bivalents are formed during meiosis and consist of two homologous chromosomes. Each bivalent represents a pair of chromosomes.

2. **Calculating Total Chromosomes**:
- Since there are 8 bivalents, and each bivalent consists of 2 chromosomes, we can calculate the total number of chromosomes in the parent cell.
- Total chromosomes = Number of bivalents × 2 = 8 × 2 = 16 chromosomes.

3. **Identifying the Diploid Number (2n)**:
- The total number of chromosomes (16) indicates that the parent cell is diploid (2n). Therefore, 2n = 16.

4. **Meiosis I**:
- During meiosis I, the homologous chromosomes (bivalents) are separated into two daughter cells.
- Each daughter cell will receive half the number of chromosomes from the parent cell.
- Number of chromosomes in each daughter cell after meiosis I = Total chromosomes / 2 = 16 / 2 = 8 chromosomes.

5. **Meiosis II**:
- Meiosis II is similar to mitosis, where the sister chromatids of each chromosome are separated.
- Since each daughter cell from meiosis I has 8 chromosomes, and each chromosome is made up of two sister chromatids, the number of chromosomes in each daughter cell remains the same after meiosis II.
- Therefore, the number of chromosomes in each daughter cell after meiosis II = 8 chromosomes.

### Final Answer:
- The number of chromosomes in daughter cells after meiosis-I: **8 chromosomes**.
- The number of chromosomes in daughter cells after meiosis-II: **8 chromosomes**.