In Drosophila the XXY constitution determines

Options

A. Maleness
B. Femaleness
C. Intersex
D. Both A and C

Answer

To determine what the XXY constitution signifies in Drosophila, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Genetic Basis of Sex Determination in Drosophila**:
- In Drosophila, sex is determined by the ratio of X chromosomes to autosomes (A). The presence of Y chromosomes does not play a significant role in determining sex.

2. **Identify the Chromosomal Constitution**:
- The given constitution is XXY. This means there are two X chromosomes and one Y chromosome.

3. **Calculate the Ratio of X to Autosomes**:
- In Drosophila, the sex determination system uses the formula:
\[ \text{Ratio} = \frac{\text{Number of X chromosomes}}{\text{Number of Autosomes}} \]
- For XXY, we have 2 X chromosomes. The number of autosomes (A) in Drosophila is typically 4 (2 pairs). Therefore, the ratio becomes:
\[ \text{Ratio} = \frac{2}{4} = 0.5 \]

4. **Interpret the Ratio**:
- A ratio of 1 (1:1) corresponds to a female, while a ratio of 0.5 (1:2) corresponds to a male. However, in the case of XXY, the presence of two X chromosomes and one Y chromosome indicates a deviation from typical male or female classifications.

5. **Conclusion**:
- The XXY constitution in Drosophila typically results in an intersex condition, where the organism may exhibit characteristics of both male and female. Therefore, the final answer is that the XXY constitution determines intersex.

### Final Answer:
In Drosophila, the XXY constitution determines intersex.