In idiogram of Drosophila, sex chromosomes are shown

Options

A. In the beginning
B. At number two position
C. At number three position
D. At the end.

Answer

To answer the question regarding the representation of sex chromosomes in the idiogram of Drosophila, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Idiograms**: An idiogram is a graphical representation of the chromosome complement of an organism. It arranges chromosomes in a standard format based on their size and shape.

2. **Chromosome Arrangement**: In an idiogram, chromosomes are typically arranged in order of size, from the largest to the smallest. This arrangement helps in identifying the chromosomes and understanding their structure.

3. **Drosophila Chromosome Count**: Drosophila, commonly known as the fruit fly, has a total of 8 chromosomes, which includes 4 pairs. Out of these, 3 pairs are autosomes (non-sex chromosomes) and 1 pair consists of sex chromosomes.

4. **Sex Chromosomes in Drosophila**: In Drosophila, the sex chromosomes are represented as X and Y. The presence of these chromosomes determines the sex of the organism, with females being XX and males being XY.

5. **Position of Sex Chromosomes in Idiogram**: In the idiogram of Drosophila, the sex chromosomes (X and Y) are typically shown at the beginning of the arrangement. This is different from humans, where sex chromosomes are placed after the autosomes.

6. **Conclusion**: Therefore, in the idiogram of Drosophila, the sex chromosomes are shown first, indicating their position at the beginning of the chromosome arrangement.

### Final Answer:
In the idiogram of Drosophila, sex chromosomes are shown at the beginning.

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