Question

What can cause several chromosomal disorders?

Answer 1

Chromosomal Disorders:

1. Every species also has a characteristic structure & number of chromosomes present.
2. Due to certain irregularities at the time of cell division, alteration in structure or number of chromosomes may happen.
3. Even the slightest alteration can also lead to various abnormalities.
4. Examples of chromosomal disorders: Down syndrome, Turner's syndrome, Trisomy 18, Trisomy 13.
5. There are two types of chromosomal abnormality: Aneuploidy and Polyploidy.

Aneuploidy:

1. Aneuploidy is the loss or gain of a chromosome.
2. Aneuploidy happens due to non-disjunction of chromatids when the chromatids fail to separate during the cell division.
3. Aneuploidy results in one gamete having 2 copies of one chromosome and the other having no chromosome.

Polyploidy:

1. Polyploidy is increase in the number of chromosomes due to failure of cytokinesis during cell division.
2. Polyploidy is seen in plants mostly.

Causes of chromosomal disorders:

1. The main cause of chromosomal disorders is an error during meiosis and mitosis.
2. Another cause of chromosomal disorders is exposure to teratogens which are the chemicals that cause abnormal foetal development.