Question

Conditions of a karyotype 2n ± 1 and 2n ± 2 are called:
a. Aneuploidy
b. Polyploidy
c. Allopolyploidy
d. Monosomy


NCERT Class XII
Biology - Main Course Book

Chapter 5. Principle of Inheritance and Variation

Answer 1

Option A  -  Aneuploidy is the answer

Answer 2

This type of condition is called Aneuploidy.

• Conditions of a karyotype 2n+1 or 2n-1 and 2n+2 or 2n-2 are called Aneuploidy, it means chromosomal abnormality in a cell.

• This condition leads to genetic syndromes including some human birth defects.

• For example, in pregnancies, aneuploidy is a condition this will leads to miscarriages.

• Chromosomal disorders occurred because of aneuploidy it is the second major category of chromosomal mutations.

• Down Syndrome is a common disorder caused due to aneuploidy.