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Biology Honors Semester 2 Final Exam > U4P2 > Flashcards

Flashcards in U4P2 Deck (25)
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what are darwin's finches an example of?

divergent evolution



evolution of two or more individuals due to each other's influence


purpose of hardy weinberg equation

calculate allele frequencies to determine whether evolution has occurred


small population

most susceptible to loss of genetic variability as a result of genetic drift


punctuated equilibrium

pattern of evolution that occurs with periods of rapid change followed by longer periods with little or no change


sympatric speciation

one location, no physical barrier


allopatric speciation

two locations, due to geographical isolation


what type of speciation occurs when new species arise as a result of a mountain range dividing a population



compare and contrast prezygotic isolation and postzygotic isolation

prezygotic- before zygote forms
postzygotic-after zygote forms; mechanical, behavioral, temporal


if one fish population is separated by a dam, the two populations may evolve into different species due to which type of isolation



bird species a and bird species b live in the same tree, but do not mate because they do not recognize each other's mating calls. what type of isolation?



disruptive natural selection

may eliminate average phenotype


certain population of cacti range i the number of needles the smallest number is 5 needles per cm squared and the high end is 15 per cm squared. due to animals eating the cacti with a lower number needles the population now ranges, from 10 per cm squared needles to 15 per cm squared needles.



praying mantis living deep in a rain forest looks almost exactly like a leaf of the tree it lives in. this is an example of what type of predation selection



temporal isolation

speciation can occur if two groups mate at different times of the year


dutch elm disease is a fungal infection of elm trees that usually results in death. the disease has killed millions of north american elm trees that were not resistant to the fungus. scientists have bred resistant elms by crossing north american species with asian species that show resistance. how does natural selection promote resistant elm populations once the resistance genes from the asian species were successfully introduced?

resistant reproducing viable offspring, population adapting


starting in 1954, commercial fishers in the northwest pacific were paid by weight, rather than by the individual fish, for pink salmon. the fishers increased the use of a type of net that selectively catches larger fish. how would you expect the body size to change over the next 20 years?



the coral snake is highly venomous snake, if bitten a human could die within a couple of hours without treatment. the kind snake isn't venomous at all but has coloration very similar to the coral. which type of selection does this example exhibit?

mimicry (predation selection)


elk antlers are used to battle other males for territory and mating rights for females. which type of selection does this example exhibit



whales have to surface to breathe. the danger with surfacing is that they become vulnerable to whale hunters. also this takes away time from trying to eat. whales that can have higher oxygen efficiency are able to hold longer and stay in deeper waters longer to avoid whalers and eat more. which type of selection does this example exhibit



in a population of 25 trees there are two alleles for height- tall (T) and short (t) and the allele frequency is 50:50. a wild fire wipes out most of the population and only two trees survive. the two survivors are homologous dominant changing the allele frequency to 100:0 for the tall allele. which term best explains this scenaario

bottleneck effect/genetic drift


structural adaptation

body parts that increase chances of survival ex. ears better for hearing


behavioral adaptation

things organisms do to survive ex. run from humans


physiological adaptation

internal responses to stimuli ex. secrete poison


when does extinction occur

when environment changes too quickly for species to adapt