Which is not true for haplodiploid sex determination ?

Options

A. It is reported in honey bees.
B. In this type , the male produces sperms by meiosis
C. They do not have a father and thus cannot have sons .
D. In this type, the unfertilized egg develops as a male by means of parthenogenesis.

Answer

To determine which statement is not true regarding haplodiploid sex determination, we will analyze each option provided in the context of the haplodiploid system, commonly observed in honeybees.

### Step-by-Step Solution:

1. **Understanding Haplodiploid Sex Determination**:
- In haplodiploid organisms, such as honeybees, males are haploid and develop from unfertilized eggs, while females are diploid and develop from fertilized eggs.

2. **Analyzing the Options**:
- **Option A**: "Haplodiploid sex determination is present in honeybees."
- This statement is true. Honeybees exhibit haplodiploid sex determination.

- **Option B**: "In this type, males produce sperm by meiosis."
- This statement is false. Males are haploid and do not undergo meiosis to produce sperm; they produce sperm through a simpler process of mitosis since they only have one set of chromosomes.

- **Option C**: "They do not have a father and thus cannot have a son."
- This statement is true. Males do not have a father because they develop from unfertilized eggs and cannot have sons since they can only produce daughters through fertilization.

- **Option D**: "In this type, unfertilized eggs develop as males by means of parthenogenesis."
- This statement is true. Males develop from unfertilized eggs through the process of parthenogenesis.

3. **Conclusion**:
- The statement that is not true regarding haplodiploid sex determination is **Option B**, as it incorrectly describes how males produce sperm.

### Final Answer:
**Option B** is not true for haplodiploid sex determination.

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