Chromosomes found in the salivary glands of Drosophila are

Options

A. polytene chromosome
B. lampbrush chromosome
C. supernumerary chromosome
D. B-chromosomes

Answer

To solve the question regarding the type of chromosomes found in the salivary glands of Drosophila, we will analyze the options provided and identify the correct answer step by step.

### Step 1: Understand the Question
The question asks about the specific type of chromosomes that are found in the salivary glands of Drosophila (fruit flies).

### Step 2: Review the Options
The options given are:
a. Polythene chromosome
b. Lambrecht chromosome
c. Supernumerary chromosome
d. B chromosomes

### Step 3: Analyze Each Option
- **Option a: Polythene chromosome**
Polythene chromosomes are known for having multiple DNA strands that have undergone replication without cell division, resulting in thick, banded chromosomes. These are indeed found in the salivary glands of Drosophila and are used for genetic studies due to their large size and distinct banding patterns.

- **Option b: Lambrecht chromosome**
Lambrecht chromosomes are associated with certain stages of development and are characterized by having multiple transcription sites. However, they are not specifically found in the salivary glands of Drosophila.

- **Option c: Supernumerary chromosome**
Supernumerary chromosomes are additional chromosomes that are not essential for survival. They can be found in various organisms but are not specifically noted for their presence in the salivary glands of Drosophila.

- **Option d: B chromosomes**
B chromosomes are extra chromosomes that can be found in some species but are not typically associated with the salivary glands of Drosophila.

### Step 4: Conclusion
Based on the analysis, the correct answer is **Option a: Polythene chromosome**, as these are specifically found in the salivary glands of Drosophila.

### Final Answer
The chromosomes found in the salivary glands of Drosophila are **Polythene chromosomes**.

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