Mutation is the inheritable change occuring in the organisms due to change in chromosome number, structure gene. The term mutation was given by Hugo de Vries. It was first observed in his experimental plant evening primerose. Oenothera lamarckiana. Mutation is following types.
(a) Genomic mutation: It is caused by change in number of chromosomes. It is two types:
(i) Euploidy
(ii) Aneuploidy
(b) Chromosomal aberration: It is due to change in chromosome structure. It is of 2 types.
(i) Intra chromosomal Modification: It is caused by breaking of chromosomal segments and their loss or gain within a single chromosome, e.g. deletion, inversion, etc.
(ii) Interchromosomal modification: Which involve two chromosomes causing loss of one and gain of other e.q duplication, translocation.
Mutation are the raw materials of evolution. Evolution absolutely depends on mutation because this the only way that new alleles and new regulatory regions are created but this seems paradoxical because most mutation that we observe are harmful, neutral or beneficial.
