1 Show Explain the statement “It is the population, not the individual, that evolves.” natural selection acts on an individual but evoloution acts on a population 2 Define the terms population, species, gene pool, adaptation a population is a group of individulas in a species at the same time and area who interbreed 3 List the five conditions that must be met for a population to remain in Hardy-Weinberg equilibrium. No mutations
4 Write the Hardy-Weinberg equation. Use the equation to calculate allele frequencies when the frequency of homozygous recessive individuals in a population is 25%. p2(TT) + 2pq(Tt) + q2(tt) = 1; p + q = 1 q = .25 5 Explain how bill depth in finches on Galapagos Island exemplify microevolution the represent the change in allele frequencies beaks did not get larger or smaller based on the drought but birds with naturally larger beaks survived thus greater frequency of large beaked alleles its an evolutionary change in a population 6 List and explain the mechanisms of microevolution Genetic Drift - chance genetic changes like s moose stepping on a few flowers in a small population Gene Flow - transfer of alles in or out of a population Natural Selection - breeding out 7 When are point mutations harmful and harmless? point mutations are bad when they make the organism less suitable but sometimes a rare mutation can make an indiviudual better suited for its enviroment 8 Explain how mice and human olfactory receptor genes, moth coloration, and clover cyanide production illustrate mutations and how natural selection can act upon each mutation. each mutation can serve a purpose to individuals in certain populations. 9 “Only natural selection leads to the adaptation of organisms to their environment.” since natural selection decides what species should survive it is the only mechanism that is able to change overall 10 Explain the role of population size in genetic drift. the smaller the population the greater the effect 11 Distinguish between the bottleneck effect and the founder effect. Know examples of each. a small population created from a larger pop tristian da cuda out of the 15 on had retinitis bottleneck killing off of a great number of the population for example the prarie chicken 12 Distinguish among directional, disruptive, and stabilizing selection. Give an example of each mode of selection. Directional selection on extreme of a phenotypic range is favored red flowers favored
by polinators so more red produce offspring 13 Explain how diploidy can protect a rare recessive allele from elimination by natural selection. recessive allele forms are hidden and not expressed so they are saved but not used so they are not killed off. heterozygocity is the reason. 14 Describe how heterozygote advantage and frequency-dependent selection promote balanced polymorphism. heterozygote allows for each gene type to be expressed but extrememes are not favored and frequency depennds on how much of the population has a trait so if you have lil of both you are more likely to survive so as the cycle continues there is an equal amount of occurance 15 Define neutral variations. Explain why natural selection does not act on these alleles. Nucleotide differences in noncoding sequences confer no advantage or disadvantage they are non encoding so natural selection doesnt effect the frecuency of the alleles 16 Distinguish between intrasexual selection and intersexual selection. intersexual one mate is picky of the other mate while intrasexual is fighting within the same sex 17 Explain how female preferences for showy male traits may benefit the female. Good gene hypothesis female slects male and off spring reproduce 18 Explain how the genetic variation promoted by sex may be advantageous to individuals on a generational time scale. the more advantageous one generation s those traits will be passed on and other preserved when needed. 19 List four reasons why natural selection cannot produce perfect organisms. Selection can act on only existing variations 20 Define relative fitness. realative fittness is based on an individuals capacity to reproduce What are the 4 conditions of natural selection?Darwin's process of natural selection has four components.. Variation. Organisms (within populations) exhibit individual variation in appearance and behavior. ... . Inheritance. Some traits are consistently passed on from parent to offspring. ... . High rate of population growth. ... . Differential survival and reproduction.. What are the 4 causes of evolution by natural selection?There are four forces of evolution: mutation, gene flow, genetic drift, and natural selection.
What are some of the reasons why evolution doesn't lead to perfection?Firstly, selection can only act on the available genetic variation. A cheetah, for example, can't evolve to run faster if there is no 'faster' gene variant available. Secondly, the body has to work with the materials it already has. It can't make something out of nothing—that's why winged horses are the stuff of myth.
What are the four reasons why natural selection Cannot fashion perfect organisms?Natural selection cannot fashion perfect organisms There are at least four reasons why:. Evolution is limited by historical constraints.. Adaptations are often compromises.. Not all evolution is adaptive.. Selection can only edit existing variations.. |