Natural Sciences CLEP Exam Questions with Complete Solutions

Evolution - ANSWER-the gradual change of characteristics within a population, producing a change in a species over time. Natural Selection - ANSWER-a feature of population genetics that is the driving force behind evolution. Gene Pool - ANSWER-the entire collection of genes within a given population. Differential Reproduction - ANSWER-individuals within a population that are most adapted to the environment and are also the most likely individuals to reproduce successfully; tends to strengthen the frequency of expression of desirable traits across the population. Mutation - ANSWER-a change of the DNA sequence of a gene, resulting in a change of the trait. Genotype - ANSWER-the combination of alleles that make a particular trait. Phenotype - ANSWER-the trait expressed. Genetic Drift - ANSWER-over time, a gene pool (particularly in a small population) may experience a change in frequency of particular genes simply due to change fluctuations. Gene Migration - ANSWER-the introduction of new genes from an immigrant, which results in a change of the gene pool. Hardy-Weinberg Law of Equilibrium - ANSWER-in situations where random mating is occurring within a population (which is in equilibrium with its environment), gene frequencies and genotype ratios will remain constant from generation to generation. Allopatric Speciation - ANSWER-occurs when two populations are geographically isolated from each other. Sympatric Speciation - ANSWER-genetically different members reproduce with each other, producing a population, which is separate from the original species. Adaptive Radiation - ANSWER-a single species can develop into several diverse species over time; over time a species will specially adapt to live more effectively in a new environment.