Answer:
Mutation occurs at random points in the bases of the DNA. Mutation happens during DNA replication either induced by environmental factors or through errors in mitosis and meiosis.
Step-by-step explanation:
Point mutation is a change of one base pair in the DNA sequence. It is a result of a mistake during DNA replication. Causes of point mutation are either spontaneous mutation or exposure to radiation. It is usually not fatal. There are three types of point mutations: nonsense (mutation to premature stop codon), missense (mutation codes for a different amino acid), and silent (mutation codes for the same amino acid).