Mutations

A Mutation is a change in genetic material There are 2 types of mutations Gene mutations Produce a change in a single gene Chromosomal mutations Produce a change in a whole chromosome

Gene Mutations Point mutation Mutations involving one or only a few nucleotides. Includes when one base is changed to another, And when one base is inserted or removed from the DNA sequence. Equivalent to changing one letter in a sentence original The fat cat ate the wee rat mutation The fat hat ate the wee rat

Gene Mutations Frameshift mutation When one or more bases are added or removed. This causes the reading frame to change or shift. This can result in a meaningless and often shortened protein. Equivalent to adding or removing letters in a sentence. original The fat cat ate the wee rat mutation The fat caa tet hew eer at (t in cat deleted)

Chromosomal Mutations Deletion Affect the whole chromosome Can be small, like the removal of one codon sequence, or larger like the removal of an entire gene on the chromosome. One example is the removal of a word. original The fat cat ate the wee rat mutation The fat ate the wee rat

Chromosomal Mutations Duplication When one part of the chromosome gets copied and inserted back into the chromosome. An example is when a word is duplicated in a sentence. original The fat cat ate the wee rat mutation The fat cat cat ate the wee rat

Chromosomal Mutations Inversion An entire section of DNA is reversed. May involve only a few bases or several genes Equivalent to part of a sentence being flipped around or inverted original The fat cat ate the wee rat mutation The fat tar eew eht eta tac

Chromosomal Mutations Translocation When part of one chromosome swaps places with part of another chromosome. This would be the same as if two sentences broke apart and recombined with each other. original The fat cat ate the wee rat The big dog ran mutation The fat cat ate dog ran The big the wee rat

Mutations Most mutations have little or no effect on gene expression. Mutations that cause dramatic changes can be harmful and disrupt normal biological activities.

Mutations Mutations may also produce proteins that have new or altered activities that can be useful. This is most often seen in plants and animals. Polyploid plants are often larger and stronger than diploid plants.

Polyploidy Polyploidy is the condition in which an organism has extra sets of chromosomes. This happens when a complete set of chromosomes fails to separate during meiosis. Gametes produced may be triploid (3N) or tetraploid (4N). Some examples of polyploid plants are bananas and many citrus fruits.