Question
Chromosomal study is best carried out in ‑
| A. |
Prophase
|
| B. |
Metaphase
|
| C. |
Telophase
|
| D. |
Anaphase
|
Show Answer
|
Correct Answer � B
Explanation
|
|
Ans. is `b’ i.e., Metaphase
Method of karyotyping
- Karyotyping is the study of chromosomes.
- Dividing cells are arrested in metaphase by the addition of colchicine or colcemid (deacetylmethylcolchicine).
- Subsequently, cells are exposed to a hypotonic solution to induce swelling of the cell for enhancing the spreading of the chromosomes.
- The metaphase cells are then fixed with a methanol/glacial acetic acid mixture and stained by one of the several banding techniques.
- After staining, chromosomes are analyzed under a microscope and photographed.
- Finally, a karyotype is constructed by a manual or automated pattern.
- Chromosomes are arranged in pairs and decreasing order of length.
