All are incorrect for fruitly, except

Options

A. could be grown on simple synthetic medium in laboratory
B. they complete their life cycle in about two days
C. it has many types of herediatary variations that can be seen with high power microscopes
D. there is clear differentiation of the sexes, males are slightly larger in size than females

Answer

To solve the question "All are incorrect for fruit fly, except," we need to evaluate each of the provided statements about the fruit fly (Drosophila melanogaster) and identify which one is correct.

### Step-by-Step Solution:

1. **Evaluate the First Statement:**
- **Statement:** "Could be grown on simple synthetic medium in laboratory."
- **Analysis:** This statement is true. Drosophila melanogaster can indeed be cultured on simple synthetic media in laboratory settings, making it a popular model organism for genetic studies.

2. **Evaluate the Second Statement:**
- **Statement:** "They complete their life cycle in about two days."
- **Analysis:** This statement is incorrect. The life cycle of Drosophila melanogaster typically takes about two weeks (14 days), not two days.

3. **Evaluate the Third Statement:**
- **Statement:** "It has many types of hereditary variations that can be seen with high power microscopes."
- **Analysis:** This statement is also incorrect. While Drosophila does exhibit many hereditary variations, these variations can be observed with low power microscopes, not exclusively with high power microscopes.

4. **Evaluate the Fourth Statement:**
- **Statement:** "There is clear differentiation of the sexes; males are slightly larger in size than females."
- **Analysis:** This statement is incorrect. In Drosophila, females are actually larger than males, which contradicts the statement.

### Conclusion:
After evaluating all the statements, the only correct statement is the first one: "Could be grown on simple synthetic medium in laboratory." Therefore, the answer to the question is the first statement.

### Final Answer:
The correct statement about fruit flies (Drosophila melanogaster) is: "Could be grown on simple synthetic medium in laboratory."

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