Question

What are mutations? How are they good ? Bad?

Answer 1

Mutations are physical changes in genes and chromosomes. They may be confined to a single cell or may be transmited from one cell to another within a multicellular organism, or from one generation to another through mutation in the gametes. Mutations may be caused by natural events within the enviroment, by action or inaction of the DNA repair enzymes, and by human production of chemicals or high-energy radiation.
Mutations can be classified in terms of the structural changes they cause, and in terms of the changes in the genetic information they produce. Point mutations are those affecting a single nucleotide. Point mutations may be deletions or insertions of nucleotides, or changes from one nucleotide to another (substitutions).