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When selection favors homozygous genotypes over heterozygous genotypes (i.e., heterozygote disadvantage)... ---------CORRECT ANSWER-----------------the most common allele will typically become fixed (will increase to a frequency of 1.0) in the population. If migration proceeds unopposed by any other evolutionary processes, the result will be ---------CORRECT ANSWER-----------------homogenization of allele frequencies among the populations involved "If a population is not in Hardy-Weinberg equilibrium..."? ---------CORRECT ANSWER-----------------the allele and/or genotype frequencies will change from one generation to the next. When selection favors heterozygous genotypes over homozygous genotypes (i.e., heterozygote advantage)... ---------CORRECT ANSWER-----------------the selective advantage enjoyed by the deleterious allele in heterozygotes balances/offsets the selective disadvantage suffered by homozygous recessive individuals.

ther recessive allele is maintained at a frequency greaster than that predicted by Hardy-Weinberg principles based on the strength of selection against the recessive allele. genetic diversity in the population can be maintained, in spite of selection acting against the recessive allele. Which of the following can maintain deleterious alleles in a population at higher than expected frequencies? ---------CORRECT ANSWER-----------------migration mutation genetic drift Many small, isolated populations demonstrate high incidences of autosomal recessive disorders. Which mechanisms best explains/creates this situation: --------

• CORRECT ANSWER-----------------Genetic Drift Inbreeding (Non-random mating) _______ theory proposes that advantageous mutations are very rare and that most alleles of genes are selectively _______. The rate of substitution for most genes will therefore be _______ to the neutral mutation rate. ---------CORRECT ANSWER-----------------neutral neutral equal

Point mutations that do not result in an amino acid change (e.g., AGU → AGC) are referred to as _______ substitutions. ---------CORRECT ANSWER----------------- synonymous Which of the following statements regarding mutation rates is true? Lower mutation rates are better than higher mutation rates. Mutation rate is usually higher for nuclear DNA than for mitochondrial DNA. Mutation rate is identical for all species. Faster DNA polymerases are associated with lower mutation rates. High mutation rates can be advantageous in novel environments. ---------CORRECT ANSWER-----------------High mutation rates can be advantageous in novel environments. In sexually reproductive organisms, mutations must occur in the _______ in order to be passed on to the next generation. ---------CORRECT ANSWER----------------- gametes When researchers grown C. elegans in environments free of Natural Selection (i.e., no competition for resources), the overall fitness of the population is observed to decrease over many generations. In environments where Natural Selection is operating (i.e., competition for resources exists), the fitness of the population is observed to remain constant over many generations. What do these findings suggest about mutations? ---------CORRECT ANSWER-----------------That

most mutations are at least slightly deleterious, and Natural Selection operates to remove such mutations from the population. Point mutations that substitute a purine for a purine (or a pyrimidine for a pyrimidine) are referred to as _______, while point mutations that substitute a pyrimidine for a purine (and vice versa) are termed _______. ---------CORRECT ANSWER-----------------transition transversion Given the allele frequencies below, what would be the expected genotype frequencies in the next generation assuming all assumptions of the Hardy- Weinberg Equilibrium Principle are being met? (Assume allele A = p, and allele a = q) Allele Frequencies: p = 0. q = 0.28 ---------CORRECT ANSWER-----------------Genotype Frequencies: AA = 0. Aa = 0. aa = 0. What are the assumptions of the Hardy-Weinberg Equilibrium Principle? --------- CORRECT ANSWER-----------------No mutations are occurring (i.e., no new alleles are being created).

q = 0. What is Evolution? ---------CORRECT ANSWER-----------------Small changes in the genes (alleles) of a population of organisms from one generation to the next. Such changes can accumulate with each successive generation. What is it about the biology and evolution of HIV that makes it such a difficult virus to develop treatments for? ---------CORRECT ANSWER-----------------Its high mutation rate leads HIV to evolve resistance to retroviral drugs rapidly, and any drugs that disrupt viral replication may disrupt host DNA replication as well. In the Florida Panther example from class, the goal of introducing the 8 female panthers from Texas was to reduce ________ and increase _______. Did this work? ---------CORRECT ANSWER-----------------inbreeding genetic variation yes Are all species related? ---------CORRECT ANSWER-----------------Yes, all currently living species on Earth share a common ancestor. Natural selection acts at the _______ level, but the repercussions are observed at the _______ level. ---------CORRECT ANSWER-----------------Individual

Population The process of evolution both explains the great amount of _______ we observe in the natural world, and well as the underlying _______ we see among all living forms. ---------CORRECT ANSWER-----------------diversity similarity Complete the following statement by Theodosius Dobzhansky" "Nothing in _______ makes sense except in the light of _______." ---------CORRECT ANSWER--- --------------biology evolution Which of the following represent synapomorphies? A. Wings in birds and bats B. Nuclear envelope in the cells of Animals, Plants and Fungi. C. Camera eyes in vertebrates and mollusks. D. Answer A and C are both correct. E. Answers A, B and C are all correct. ---------CORRECT ANSWER-----------------B. Nuclear envelope in the cells of Animals, Plants and Fungi.

Natural selection acts on _______, but evolution consists of changes in _______ frequencies. ---------CORRECT ANSWER-----------------phenotypes allele A monophyletic group includes a common ancestor and all of its ---------CORRECT ANSWER-----------------descendants When two or more groups of organisms have coevolved over hundreds of thousands or millions of years, you would expect their evolutionary trees to reflect... ---------CORRECT ANSWER-----------------evolutionary histories that mirror one another and shared speciation events The creationist "argument from design" is based on the idea that complex structures (like vertebrate eyes) and organisms can't arise by chance. This argument fails because, although _______ is random, _______ is not; it is a cumulative process that is directed in the sense of increasing adaptation. --------- CORRECT ANSWER-----------------mutation natural selection The radio/TV personality Larry King once asked an evolutionary biologist "If evolution is real, why are there still monkeys?" While this question is ill-informed at best, it demonstrates which misconceptions about evolution? ---------CORRECT ANSWER-----------------That evolution proceeds in a stepwise fashion, such that one organism replaces its ancestors as it evolves and that humans evolved from monkeys (same as saying that dogs evolved from wolves)

Using the observed allele frequencies you just calculated above, determine the expected genotype frequencies in the next generation (assuming no violations of the Hardy-Weinberg principle). ---------CORRECT ANSWER-----------------BB = 0. Bb = 0. bb = 0. Is this population in Hardy-Weinberg equilibrium? ---------CORRECT ANSWER-------- ---------No One of the most important sources of new genes is likely _______. The most common underlying mechanism for this process is _______. ---------CORRECT ANSWER-----------------gene duplications / unequal crossing-over In a heterzygote advantage situation, a less fit or lethal allele remains in the population at _______ than expected frequencies. This is because the homozygous genotypes both have _______ fitness than heterozygous genotype. - --------CORRECT ANSWER-----------------higher lower

Which mechanism does not have the potential to change allele frequencies within a population from one generation to the next? ---------CORRECT ANSWER------------ -----Non-random mating Inbreeding increases the frequency of _______ genotypes in a population, and reduces the frequency of _______ genotypes. ---------CORRECT ANSWER------------- ----homozygous heterozygous A trait can be assumed to be an adaptation if... ---------CORRECT ANSWER------------ -----it is shown, in a well-designed scientific study, to have a function and to increase fitness of individuals that have the trait. The hypothesis that a given trait represents a "trade-off" implies that --------- CORRECT ANSWER-----------------The trait is the result of conflicting selection pressures. T or F: The differences we see between populations or species are always adaptive. ---------CORRECT ANSWER-----------------False T or F: Not every trait, or use of a trait, is an adaptation ---------CORRECT ANSWER- ----------------True

T or F: Not every adaptation is perfect ---------CORRECT ANSWER-----------------True Darwin referred to the differential reproductive success due to variation among individuals in their ability to attract or secure mates as _______ selection. --------- CORRECT ANSWER-----------------sexual The amount of time and energy expended by an organism to produce and care for offspring as _______ investment. ---------CORRECT ANSWER-----------------parental In situations where intersexual selection is acting upon a population, members of the sex experiencing strong sexual selection will be _______ with one another. Members of the sex that is subject to weak sexual selection will be _______. ------- --CORRECT ANSWER-----------------competitive choosy In the Begonia involucrata flower size example from lecture, the fact that female plants are not able to make many large flowers, but instead make many small flowers, is an example of ---------CORRECT ANSWER-----------------Physiological constraint

Two individuals of this species can produce viable, fertile offspring: --------- CORRECT ANSWER-----------------biological species concept Smallest diagnosable group of individuals that share a recent common ancestor: -- -------CORRECT ANSWER-----------------phylogenetic species concept A group of individuals all adapted to a specific set of resources: ---------CORRECT ANSWER-----------------ecological species concept Individuals of this species share specific phenotypic features: ---------CORRECT ANSWER-----------------morphological species concept For a system of reciprocal altruism to evolve and function, specific conditions must be satisfied. As we discussed in class, the presence of cheaters (i.e., individuals that accept help but do not return the favor) can bring the whole system down. This is because: ---------CORRECT ANSWER-----------------Alleles for cheating will increase in frequency due the low cost, high benefit associated with cheating. What is the order of occurrence of the steps of speciation? ---------CORRECT ANSWER-----------------Isolation of populations

Genetic divergence Reproductive isolation Which of the steps of speciation may or may not occur during the speciation process? ---------CORRECT ANSWER-----------------Reproductive isolation Which of the following statements regarding reinforcement is correct? It is essential for speciation to occur. It must be the first step in speciation in order for the process to go to completion. It can occur when closely related species come back into contact and hybridize, and when hybrids have reduced fitness. It can only occur when closely related species are isolated by physical barriers to gene flow. It can lead to the production of a new species when backcrossing with parents produces more fit offspring. ---------CORRECT ANSWER-----------------It can occur when closely related species come back into contact and hybridize, and when hybrids have reduced fitness. Current research indicates that the most common mechanism leading to genetic divergence between two isolated populations is: ---------CORRECT ANSWER---------- -------natural selection

A novel phenotypic trait (i.e., flowers) that allows a lineage or group to radiate and diversify is known as a ---------CORRECT ANSWER-----------------key innovation When a single or small group of ancestral species rapidly diversifies into a large number of descendant species that occupy a wide variety of ecological niches, this is known as an ---------CORRECT ANSWER-----------------adaptive radiation The biggest issue facing the successful production of influenza vaccines is that... -- -------CORRECT ANSWER-----------------influenza A populations evolve rapidly flu vaccines take months to develop researchers must successfully determine which strain is most likely to survive and be the dominant strain next season When the ancestors of Hawaiian honeycreepers arrived in Hawaii they radiated into over 50 species, filling the available niches in this new environment. This is an example of an _______ factor driving the diversification rate. ---------CORRECT ANSWER-----------------external/ecological During hybridization, the phenomenon in which gametes from the same species are preferentially selected to produce zygotes, is known as... ---------CORRECT ANSWER-----------------Gametic isolation

When a male donkey mates with a female horse, the result is sterile offspring know as a mule. This is an example of a _______ isolating mechanism. --------- CORRECT ANSWER-----------------Postzygotic Although closely related, males of the Lesser Pahoa Jabberwocky do not have the appropriate genitalia to successfully fertilize females of the Greater Pahoa Jabberwocky. This is an example of a _______ isolating mechanism. --------- CORRECT ANSWER-----------------Prezygotic Studies of the influenza A virus have shown that... ---------CORRECT ANSWER-------- ---------selection by the immune system drives change in hemagglutinin's antigenic sites