Academic Biology Notes Mutations Academic Biology Notes

What is a mutation? Mutations- changes in genetic material “Mistakes” when copying DNA Come in many shapes and sizes

Kinds of Mutations: gene mutations Point Mutations Gene mutations that involve changes in one or few nucleotides. Occur at a SINGLE point in a DNA sequence SUBSTITUTIONS- 1 base is changed into another INSERTIONS- 1 base is inserted DELETIONS- 1 base is deleted

KINds of mutations: Gene mutations Substitutions, Insertions, and Deletions are also known as FRAMESHIFT MUTATIONS. FRAMESHIFT MUTATIONS shift the reading of the genetic message. Order of amino acids may change.

Gene Mutations (Frameshift mutations)

Kinds of mutations: chromosomal mutations Involve changes in the number or structure of the chromosomes 4 Types of Chromosomal Mutations: 1.DELETIONS- the loss of all or part of a chromosome 2.DUPLICATIONS- extra copies of parts of a chromosome 3.INVERSIONS- reverse the direction of parts of a chromosome 4.TRANSLOCATIONS- part of 1 chromosome breaks off and attaches to another

Why are mutations important? Many mutations are neutral. (Little or no effect on gene expression or protein function) Some mutations are harmful. Mutations provide variety among species.