Basics of Mutations Topic 3034 Torey Birchmeier

Mutations n A sudden change in the characteristics of an organism due to a change in the chemical structure of the DNA. n The change must be capable of being transmitted fully to future generations without change.

Mutation n An example of a mutation is the polled characteristic in beef cattle.

Causes of Mutations n An error in DNA replication n Exposure to radiation n Exposure to certain toxic or poisonous chemicals n Other genetic abnormalities such as extra chromosomes or chromosomes crossing or breaking

Mutations in Evolution n Mutations are recognized as the primary source of the hereditary variations that make evolution possible. n Mutations can either be harmful or useful to species.

Mutations in Evolution n Mutations that help an animal survive are continued because survivors reproduce and pass the gene on to their offspring. n Mutations that are harmful to a species are less likely to be passed on because the animals do not survive or reproduce.

Mutations in Commercial Agriculture n A Perfect Example…….. n A natural occurring mutation or change occurred in the horse. n Over many years the horse’s hoof characteristics changed to suit a changing environment.

Mutations in Commercial Agriculture n The one hooved horse today is much more useful to agriculture than its smaller four toed counterpart “eohippus” which lived long ago.

Other Mutation Examples n Rust resistant wheat n Plant breeders have taken advantage of natural selection for a strain of rust resistant in wheat. n Breeders have breed this trait into other wheat strains to help aid in agriculture production

Other Mutation Examples n High protein corn n Geneticists have selected for high protein varieties and have tried to breed them exclusively n This selection is “manmade” rather than based on “natural selection” such as the horse

References n Cow Picture: n DNA Picture: n Horse Picture: