Principles of Inheritance and Variations — BIOLOGY STD 12 Science — Question

Genetic variation arises by mutation : The mutation may be defined as "alternation in the arrangement, or amount of genetic material of a cell or a virus." They may be classified as either point mutations involuing minor changes in the genetic material or macromutation (e.g., deletion) involuing larger section of chromosomes. Example of a mutation : Sickle cell anemia.