How many meiotic divisions are required during the formation of 500 zzygotes, if in males one meiotic division result in formation of four male gametes and in females one meiotic divison results in formation of one female gamete?

Options

A. 625
B. 500
C. 1000
D. 2500

Answer

To solve the problem of how many meiotic divisions are required to form 500 zygotes, we can break down the solution into clear steps.

### Step-by-Step Solution:

1. **Understanding Zygote Formation**:
- A zygote is formed when one male gamete fuses with one female gamete. Therefore, to form 500 zygotes, we need 500 male gametes and 500 female gametes.

2. **Calculating Male Gametes**:
- In males, one meiotic division results in the formation of 4 male gametes.
- To find out how many meiotic divisions are needed to produce 500 male gametes, we can use the unitary method:
\[ \text{Number of meiotic divisions required} = \frac{\text{Number of male gametes needed}}{\text{Male gametes produced per division}} = \frac{500}{4} = 125 \]
- Thus, 125 meiotic divisions are required to produce 500 male gametes.

3. **Calculating Female Gametes**:
- In females, one meiotic division results in the formation of 1 female gamete.
- Therefore, to produce 500 female gametes, we need:
\[ \text{Number of meiotic divisions required} = \frac{\text{Number of female gametes needed}}{\text{Female gametes produced per division}} = \frac{500}{1} = 500 \]
- Thus, 500 meiotic divisions are required to produce 500 female gametes.

4. **Total Meiotic Divisions**:
- Now, we add the number of meiotic divisions required for both male and female gametes:
\[ \text{Total meiotic divisions} = \text{Meiotic divisions for male gametes} + \text{Meiotic divisions for female gametes} = 125 + 500 = 625 \]

5. **Final Answer**:
- Therefore, the total number of meiotic divisions required to form 500 zygotes is **625**.