Wednesday January 5, 2011 Original DNA Strand: CATCATCAT Warm-Up: Which of the following is an example of a single base change from the original DNA strand above? A.) CAT CAGGCTCAT B.) CATCCAT C.) CATCATCAT D.) CATCCTCAT Selective Breeding • • Selective breeding allows only those organisms with desired characteristics to produce the next generation. Examples: Dog breeds, corn, tomatoes, crops, flowers Hybridization • Hybridization is the crossing of dissimilar individuals to bring together the best of both organisms. Examples: Horse + Donkey = Mule Hybrids are always sterile Inbreeding • • • • Inbreeding is the continued breeding of individuals with similar characteristics. Serious genetic problems can result from excessive inbreeding. Examples: Mating between closely related individuals In Humans, it is called incest. Genetic Variation Genetic variation is the variation in the genetic code. Populations need to have high genetic variation among individuals to prevent harmful mutations. 13-1 The usual function of selective breeding is to produce organisms that • • • • are better suited to their natural environment. have characteristics useful to humans.** can compete with other members of the species that are not selected. are genetically identical. 13-1 The function of inbreeding is to produce organisms that • • • • are more genetically diverse. are much healthier. are genetically similar.** will not have mutations.