SCIN130 Chapter 15 Test Questions with Correct Answers

SCIN130 Chapter 15 Test Questions with Correct Answers Natural Selection - Answer-the process that results in adaptation of a population to the biotic and abiotic environments. Polygenic - Answer-controlled by more than one pair of alleles located at different gene loci Directional Selection - Answer-occurs when an extreme phenotype is favored and the distribution curve shifts in that direction. Example: resistance to antibiotics and pesticides Stabilizing Selection - Answer-Occurs when an intermediate phenotype is favored. Individuals near the average are favored. *Most common form of selection* Example: bird clutch size Disruptive Selection - Answer-Two or more extreme phenotypes are favored over any intermediate phenotype. Favors polymorphism-the occurence of different forms in a population of the same species. Example: Snails banding or no banding. Sexual Selection - Answer-adaptive changes in males and females that lead to an increased ability to secure a mate. Females favor male with best fitness. Males demonstrate with colors or mating rituals. Maintenance of Variations - Answer-Populations always show genotypic variation. Maintenance of variation is beneficial because populations with limited variation may not adapt to new conditions. Mutation - Answer-generates new alleles Recombination and Independent Assortment - Answer-shuffle the alleles during gametogenesis Fertilization - Answer-creates new combinations of alleles from those present in the gene pool Microevolution - Answer-the accumulation of a small gradual evolutionary changes within a population over generations