If the egg of sexually reproduction organisms contains 16 chromosomes, what will be the number of dyads in anaphase l?

Options

A. 16
B. 8
C. 32
D. 64

Answer

To solve the question regarding the number of dyads in anaphase I when the egg of a sexually reproducing organism contains 16 chromosomes, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Chromosome Count**:
- The egg (female gamete) has 16 chromosomes. Since gametes are haploid, this means that the organism's diploid somatic cells will have double this number.
- Therefore, the diploid number of chromosomes (2n) = 16 (haploid) x 2 = 32 chromosomes.

2. **Identify the Process of Meiosis**:
- Meiosis consists of two main stages: Meiosis I and Meiosis II. During Meiosis I, homologous chromosomes pair up and undergo recombination.

3. **Formation of Tetrads**:
- During prophase I of meiosis, homologous chromosomes pair up to form structures called tetrads. Each tetrad consists of four chromatids (two homologous chromosomes, each made up of two sister chromatids).
- Since the diploid cell has 32 chromosomes, it will form 16 tetrads (32 chromosomes / 2 = 16 tetrads).

4. **Understanding Dyads**:
- A dyad refers to a pair of sister chromatids. When the tetrads separate during anaphase I, each tetrad splits into two dyads.
- Therefore, if there are 16 tetrads, they will separate into 32 dyads (16 tetrads x 2 dyads per tetrad = 32 dyads).

5. **Conclusion**:
- The number of dyads present in anaphase I will be 32.

### Final Answer:
The number of dyads in anaphase I is **32**.