NEETZoologyPrinciples of Inheritance and Variation
What does polyploidy involve?
Options
- ALoss of a chromosome
- BGain of an extra chromosome
- CIncrease in a whole set of chromosomes
- DAbnormal arrangement of chromosomes
Correct answer
C. Increase in a whole set of chromosomes
Step-by-step solution
The chromosomal disorders on the other hand are caused due to absence or excess or abnormal arrangement of one or more chromosomes. Failure of segregation of chromatids during cell division cycle results in the gain or loss of a chromosome(s), called aneuploidy. For example, Down’s syndrome results in the gain of extra copy of chromosome 21. Similarly, Turner’s syndrome results due to loss of an X chromosome in human females. Failure of cytokinesis after telophase stage of cell division results in an increase in a