Chapter 14 and 15 Exam 1 Bio 102

michelleburkee2's version from 2016-02-18 05:31

Section 1

Question Answer
what is the difference between analogous structures and homologous structures?Homologous structures are structures that are similar in species that can evolutionary ties, but analogous structures are structures that are similar in unrelated species
example of homologous structureleg of lamb and dog
example of analogous structurewings on bird and insect
example of vestigial structurethe pelvic bone of a whale, the wisdom teeth of people
convergent evolutionsimilar environmental pressures caused the anatomy of unrelated species to have similar structures
descent with modificationdifferences resulting from evolutionary change during descent from a common ancestor (related species)
embryonic similarityall vertebrate embryos resemble eachother in early development
how does embryoic similarity prove evolution?humans and fish both have tails and gill slits in the womb. Humans are not born with either of these things but fish are. this proves evolution because our embryos are so similar.
what are the 4 biochemical and genetic evidence that support evolution1. DNA os used as the genetic blueprint 2.) use RNA for translation 3.)use same set of 20 amino acids to build proteins 4.) use ATP to transfer energy
homologous genesgenes with similar sequences in different species
what are two pieces of evidence that populations evolve by natural selection?controlled breeding modifies organisms and evolution by natural selection occurs today
artificial selectionselective breeding to produce plants and animals with desireable traits (ex. dog breeds)
what does natural selection rely on?variations caused by spontaneous DNA mutations
antibiotic resistant bacteria is an example of natural selection becausebacteria reproduces quickly. If an antibiotic is introduced to bacteria then most of the bacteria will be killed, but the resistant bacteria will survive and reproduce to form a population of resistant bacteria
trinidadian guppies natural selection examplefemale guppies prefer to mate with brightly colored males but the brightly colored males are more likely to be eaten by predators. Brightly colored males live in areas with less predators and unbrightly colored males live in places with more predators.
evolutionchange of characteristics in a POPULATION over time
provides an explanation for the similarities found among different types of organismsevolution
DNA of humans and chimpanzees differs by 5%
DNA of C. elogens is conserved in humans at _________%35%
who developed evolution by natural selection?Darwin

Section 2

Question Answer
example of descent with modificationhomologous structures
example of convergent evolutionanalogous structures
as animals evolved into new habitats, some of their structures that made them less fit were reduced to the point of insignificancevestigial structures
4 factors of evolutionvariance, inheritance, unequal reproduction, and survival
varianceindividuals in a population are different from one another
inheritanceindividuals inherit traits from their parents
unequal reproductionsome individuals are unable to reproduce while others are. this could be because some individuals die before they get the chance to reproduce
survivalthe individuals that are the best fit will survive and reproduce
More organisms are born than those who ____survive
in the competition to survive and reproduce, are the winners chosen by chance?no. they are chosen by the traits that they posess
natural selection modifies _________populations over time
how old approximatley is earth?4.5 billion years old
populations evolve by natural selection

Section 3

Question Answer
which is an example of descent with modification: homologous or analogous structureshomologous
which is an example of convergent evolution: homologous or analogous structuresanalogous
does natural selection modify individual organisms?no
does natural selection modify populations?yes
the unifying theme of all biologyevolution by natural selection
relevance of fossils to evolutionshows that life has changed over time. Also led to the conclusion that different species lived at different periods of time
theory of acquired characteristics wasrejected because individual organisms cannot evolve but a species evolves over time
the total of all the alleles of all the genes in a populationgene pool
different alleles=different reproductive success
what type of selection is this an ex. of: favoring resistant bacteria betterdirectional selection
what type of selection is this an ex. of: favoring average sized lizards b/c too small has no defense and too big is visible to predatorstabilizing selection
what type of selection is this an example of: favoring birds with large and small beaks because they both are beneficialdisruptive selection

Section 4

Question Answer
what is this an example of: the legs of a dog and sheephomologous structures
what is this an example of:the pelvic bone of a whale vestigial structure
what is this an example of:the wings of a bird and insectanalogous structure
how does a population change due to natural selection?traits that are adventageous are inherited at a larger scale over time
4 things that support evolution arefossils, comparative anatomy, embryological similarity, and biochemical and genetic analyses
Bb is heterozygous
BB is homozygous
population geneticsdeals with the frequency, distribution, and inheritance of alleles in populations
gene poolthe total of all the alleles of all genes in a population
allele frequencyfor any given gene, the relative proportion of each allele of that gene in a population
Example of allele frequency,population of 25 hamsters has 50 alleles of the coat color gene (diploid). What is the frequency of B if 20 of the alleles are B? What is the frequency of b?20/50= .4=40%...... 100-40= 60%
evolution is the change of _______ frequencies in populationsallele frequencies
what does it mean that the population is evolving?that allele frequencies are changing from one generation to the next
what does it mean that the population is not evolving?the allele frequencies are NOT changing from one generation to the next
casual observer defines evolution aschanges in outward appearance or behaviors over time
population genenecist defines evolution aschanges in allele frequencies in a gene pool over time
can population equilibrium occur is there is gene flow between populations? (movement of individuals into or out of the population)no
can equilibrium population occur if there are mutations in the population?*no*
can population equilibrium occur if there are no mutations in the population?yes
can population equilibrium occur if there is no gene flow in the population?*yes*
can population equilibrium occur if mating is completely random?^yes^
can population equilibrium occur if mating is not completely random?^no^
can population equilibrium occur if the population is small?%no%
can population equilibrium occur if the population is large?%yes%
can population equilibrium occur when there is natural selection?#no#
can population equilibrium occur when there is no natural selection?#yes#

Section 5

Question Answer
comparative anatomy with shared ancestryhomologous structures
comparative anatomy WITHOUT shared ancestryanalogous structures
biochemical and genetic analyses (4 things)1. DNA 2. RNA 3. same 20 amino acids used 4. ATP used for energy
provide evidence of evolutionary change over timefossils
gives evidence of descent with modificationcomparative anatomy
suggest common ancestryembryological development
suggests relatedness among diverse organismsbiochemical and genetic analyses
populationgroup that includes all members of a species in a given area
in diploid individuals, each gene consists of2 alleles
homozygousindividuals with two of the same alleles (i.e. BB or bb)
heterozygousindividuals with two different alleles (i.e. Bb)
_____ determines _______ (phenotype, genotype)genotype determines phenotype
genea segment of DNA at a specific place on a chromosome
Hardy-Weinberg principlein certain conditions the allele frequencies and genotype frequencies will not change even after many generations
equilibrium populationpopulation in which allele frquencies DO NOT change from generation to generation
the source of new allelesmutations
gene flow between populations changes _____allele frequencies
increases genetic similarity between different populations of a speciesgene flow
what can be caused by the complete block of gene flow between two populations of species?the genetic differences may grow so much that they become two different species
a change in allele frequencies of a population purely by change (gene flow or genetic drift)genetic drift
can genetic drift effect small populations?yes
can genetic drift effect large populations?no
_______ populations are more vulnerable to random eventssmall populations
nonrandom mating increases ______ frequenciesgenotype freuquencies. not allele frequencies

Section 6

Question Answer
what is it called when a population's allele frequencies DO NOT change from generation to generation?equilibrium population
equilibrium population can be maintained if these 5 things occur:no mutations occur in the population, no gene flow between populations, population must be very large, mating must be random, and there can be no natural selection ( genotypes reproduce with equal success
5 major causes of evolutionary change:mutation, gene flow, small population size, non-random mating, natural selection
mutationschanges in DNA sequence
are mutations common?no they are rare
how are mutations passed on?mutations must occur in gametes to be passed on
___ between populations changes allele frequenciesgene flow
what is the cause of gene flow?movement of individuals between populations or through pollen and seeds
genetic drifta change in allele frequencies of a population purely by chance
genetic drift effectssmall populations
large populations are more stable therefore less likely to expierence genetic drift
2 types of genetic driftpopulation bottleneck and founder effect
what is population bottleneck?drastic reduction in population size brought about by a natural catastrophe or overhunting. can rapidly change allele frequencies and reduce genetic variation
what is the founder effect?
ex. of population bottleneckelephant seals were hunted to near extinction but now their population size is back up. the seals are now very similar because there was a lack in genetic variation
founder effecta reduction of genetic variation that happens when a smal number of individuals start a new population
ex. of the founder effectamish descended from 200 people. some genetic syndromes are much more common in the amish community than the whole community. (6 fingers on one hand)
organisms in a population _____ mate randomlyrarley
interbreeding increases the chance of producingharmful homozygous alleles in offspring
nonrandom mating occurs because oflimited mobility (interbreeding) and mating bias
will interbreeding and biased mating alone alter the allele frequencies in a population?no but they can have large effects on the distribution of genotypes/ phenotypes
assortative matingpreference for mates who are similar
example of assortative matinggeese that favor mates of the same color
favors individuals at one extreme traitdirectional selection
favors individuals at average value of a traitstabilizing selection
favors individuals at both extreme forms of a traitdisruptive selection

Section 7

Question Answer
are all genotypes equally beneficial?no. natural selection favors certain alleles at the expense of others
mutationscreate new alleles. increases variation
gene flowincreases similarity of different populations
genetic driftrandom change of allele frequencies. can eliminate alleles
nonrandom matingchanges genotype frequencies but NOT allele frequencies
natural and sexual selectionincreases frequency of favored alleles. Produces adaptations
does natural selection act directly on pheotypes or genotypes?acts directly on phenotypes. Acts indirectly on genotypes
competition among the same or different species is the most intense and why?amoungs organisms of the same species because they require the same things
what type of relationships generate strong coevolutionary forces?predator-prey relationships
mutualistic relationshipboth parties benefit from the relationship. i.e. hummingbirds and flowers. Hummingbirds eat stuff from the flower and the flower gets pollinated.
predationinteraction where one organism eats another organism
sexual selectionfavors traits that help organisms acquire mates
directional selectionoccurs when environmental conditions change in a consistent way. favors individuals at one extreme trait. (ex. if antibiotics are around resistant bacteria will reproduce better)
stabilizing selectionoccurs when organisms are well-adapted and changes are harmful. favors individuals with average value of a trait. ex.) lizard size too small= no defense too big= visible to prey
disruptive selectionoccurs in an environment with more than one useful rescource. favors individuals at both extremes. Ex. bird beaks. large= seed cracking small= seed manipulation
what happens to populations over time with directional selection (ex. larger size favored)average phenotype shifts to larger size over time
what happens to populations over time with stabilizing selectionaverage phenotype does not change. phenotypic variability declines
what happens to populations over time with disruptive selectionpopulations divide into two phenotypic groups over time

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