In XO type of sex determination

Options

A. males produce two different types of gametes
B. females produce two different types of gametes
C. males produce gametes with Y chromosome
D. females produce gametes with Y chromosome

Explanation

**Step-by-Step Solution:**

1. **Understanding XO Type of Sex Determination:**
- In XO type of sex determination, the male has one X chromosome and no second sex chromosome (represented as O), while the female has two X chromosomes. This is commonly observed in certain insects, such as grasshoppers and crickets.

2. **Identifying Heterogamity:**
- Heterogamity refers to the production of two different types of gametes by one sex. In the case of XO type, the male produces two types of gametes: one with the X chromosome and one without any sex chromosome (O).

3. **Analyzing the Options:**
- Option A states that the male partner produces two different types of gametes. This is correct because the male produces gametes with either one X chromosome or no chromosome (O).
- Option B states that the female partner produces two different types of gametes. This is incorrect because the female produces only one type of gamete, which carries an X chromosome.
- Option C states that the male produces a gamete with one Y chromosome. This is incorrect because, in XO type, males do not have a Y chromosome; they only have one X chromosome and one O.

4. **Conclusion:**
- Based on the analysis, the correct answer is that the male partner produces two different types of gametes (one with X and one with O).

**Final Answer:**
- The correct option is A: The male partner produces two different types of gametes.

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