KEY Study Guide Topic # 3034 Mutations Created by Torey Birchmeier 1. Define what a mutation is. A sudden change in the characteristics of an organism due to a chamge in the chemical structure of the DNA. 2. Explain what the gene must be capable to do. The gene must be capable of being transmitted faithfully without change to the next generation. 3. List the four causes of a mutation. An error in replication Exposure to radiation Exposure to certain toxic poisonous chemicals Other genetic abnormalities such as extra chromosomes or chromosomes crossing or breaking 4. Recall if mutations are helpful or harmful and how they are passed on or not passed on. Mutations are both harmful and helpful. If the mutation is harmful to a species it is less likely to be passed on to a future generation because the animal is less likely to survive. If the mutation is helpful to a species, it is passed on because the survivors reproduce and pass the traits on to their offspring. 5. Explain the concept of the naturally occurring mutation in the horse. Over the years the horse’s hoof characteristics changed to suit the changing environment. The one hoofed horse today is more useful to agriculture than the four toed animal which lived long ago. 6. Explain the two different types of mutations plant breeders have developed and the consequences of each. Rust resistant wheat-plant breeders have taken advantage of a natural mutation for a strain of rust resistance in wheat. They have breed this trait into other wheat strains to help increase agriculture production. High protein corn-Plant breeders have located the gene in corn plants that has allowed corn plants, when the gene is inserted, produce higher protein corn. This is a man-made selection.