Question

Which of the following is not an aneuploidy?

• A. Monoploid
• B. $2n-1$
• C. Trisomic
• D. $2n+2$

Answer 1

The correct option is A Monoploid

Aneuploidy is the presence of an abnormal number of chromosomes in a cell.

2n-1 and 2n+1 corresponds to "one chromosome less than normal count" and "one chromosome extra than the normal count" respectively. Both these represent abnormal number of chromosomes. Also, A trisomy is a type of polysomy in which there are three instances of a particular chromosome, instead of the normal two. A trisomy is also a type of aneuploidy (an abnormal number of chromosomes). Monoploid has no abnormality of related to number of chromosomes.

So, the correct answer is 'Monoploid'.