Which statement is not true for Drosophila melanogaster-

Options

A. They complete their life cycle in about two weeks.
B. Single mating produce a large number of progeny flies.
C. It has few hereditary variations that can be seen with a high power microscope.
D. It has a clear differentiation of the sex.

Answer

To determine which statement is not true for Drosophila melanogaster, we will analyze each statement provided in the question.

1. **Statement 1: They complete their life cycle in about two weeks.**
- Drosophila melanogaster is known for its short life cycle, which typically lasts about 14 days (approximately two weeks) under optimal conditions. Therefore, this statement is **true**.

2. **Statement 2: Single mating produces a large number of progeny flies.**
- Drosophila is known for its prolific breeding capabilities. A single mating between a male and a female can result in a large number of offspring. Thus, this statement is also **true**.

3. **Statement 3: It has few hereditary variations that can be seen with a high power microscope.**
- This statement is misleading. Drosophila melanogaster is widely used in genetic studies because it exhibits a significant amount of hereditary variation. These variations can be observed even with a low power microscope, not just a high power one. Therefore, this statement is **not true**.

4. **Statement 4: It has clear differentiation of sex.**
- Drosophila exhibits sexual dimorphism, meaning that males and females can be easily distinguished based on their physical characteristics. This statement is **true**.

Based on the analysis, the statement that is not true for Drosophila melanogaster is: **"It has few hereditary variations that can be seen with a high power microscope."**