Salivary glands chromosome were discovered by Balbi- ani (1881) from the salivary glands oflarva of

Options

A. Chironomus
B. Drosophila
C. Silkworm
D. Lac worm

Answer

**Step-by-Step Solution:**

1. **Understanding the Term "Salivary Gland Chromosome":**
- Salivary gland chromosomes are also referred to as polytene chromosomes. They are large chromosomes that consist of many strands, which are formed by the replication of DNA without cell division.

**Hint:** Remember that "polytene" means many strands, indicating the structure of these chromosomes.

2. **Historical Context:**
- The discovery of salivary gland chromosomes was made by a scientist named Balbiani in the year 1881.

**Hint:** Focus on the year and the scientist's name as key details in the history of chromosome discovery.

3. **Source of Discovery:**
- Balbiani discovered these chromosomes in the salivary glands of the larvae of a specific insect.

**Hint:** Think about the type of organism that typically has salivary gland chromosomes; they are commonly found in insect larvae.

4. **Identifying the Insect:**
- The specific insect from which Balbiani discovered the salivary gland chromosomes is Chironomus plumosus, a type of midge.

**Hint:** Remember that Chironomus plumosus is a key example of an insect where these chromosomes can be found.

5. **Other Examples:**
- While Balbiani discovered them in Chironomus plumosus, polytene chromosomes can also be found in the larvae of other insects, such as Drosophila (fruit flies).

**Hint:** Consider that there are multiple species where these chromosomes are present, but focus on the one mentioned in the question.

**Final Answer:**
Salivary gland chromosomes, also known as polytene chromosomes, were discovered by Balbiani in 1881 from the salivary glands of the larvae of Chironomus plumosus.

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