BIOL 214 Final Exam 2020/2021 Questions and Answers

A Galton Plot is the old name for parent-offspring regression. Why was Galton's work so significant? - Because it was the first effort to estimate the degree to which a quantitative trait has a genetic basis A neutral marker is one which is not undergoing any...? - Selection A review of selection gradients estimated in natural populations found that...? - Selection gradients are typically weak to moderate, usually well below 0.5 A substitution of adenine for guanine could results in what? (4) - 1) a transition 2) a synonymous mutation 3) a non synonymous mutation 4) a point mutation **Does NOT result in an indel (insertion or deletion) A trait is said to be quantitative if...? - There are many different genes, each of which has a small effect, that contribute to the phenotype About how many loci are involved in determining human height? - 425 After gene duplication, what is NOT a likely outcome for the new gene copy? - Being rapidly lost As a population mean phenotype nears an adaptive peak, what happens to selection? - The selection gradient weakens and selection transitions from directional to stabilizing Before the advent of molecular genetic methods being used to assess genetic variability in natural populations, what did evolutionary biologists think? - Because selection depletes genetic variability over time, there should be little genetic variation Can evolution occur without natural selection? - Yes Can natural selection occur without evolution? - Yes Does natural selection ALWAYS result in evolution? - NO Does natural selection operate on phenotypes? - Yes Evolution is often portrayed as a progressive process, leading to an ideal type. Now that we have studied more complex and therefore, more realistic models of evolution, why might this NOT always be true, assuming a trait is under selection? (3) - 1) a trait might be unable to evolve further because of a lack of genetic variation 2) A trait might be negatively genetically correlated with another trait 3) the environment is always changing, which means the adaptive landscape is not constant How can plasticity facilitate the evolution of mean trait value in a population TOWARDS a fitness peak? - If plasticity is cogradient, different loci will be exposed to the effects of selection, permitting more rapid evolution towards the fitness peak How do you find polymorphic loci from a genotypic frequency data table? - (# loci with more than one type of allele frequency) / (total loci)