honors biology chapters 16-18 test questions

gradualism

"speciation may occur because of accumulation of many minor genetic changes in a population." this statement is associated with:

punctuated equilibrium

"speciation may occur rapidly and is caused by a few genetic changes in important genes." this statement is associated with:

founder effect

*isolated island, all brown eyes, one person has recessive gene for blue eyes.* after several generations, 35 percent of the population has AB+ blood. this is much higher than percent of AB+ blood in original settlers. the high percent of AB+ blood is likely due to ____.

genetic drift

*isolated island, all brown eyes, one person has recessive gene for blue eyes.* no new ppl arrive, and nobody leaves the island. after a few generations, the percent of blue eyed ppl increased from 0 to 25. this is likely due to ______.

stabilizing

________ selection favors individuals with average phenotypes over those with extreme phenotypes

genetic variability is diminished

a bottleneck may be very dangerous to a population because:

a species

a group of similar organisms that can successfully interbreed

they lack homologous chromosome and cannot undergo meiosis

a horse has 2n = 4 and a donkey has 2n - 62. the hybrid of these two species, the mule, has 63 chromosomes and is sterile. why are mules sterile?

natural selection

a population of deer was threatened with overpopulation until cheetahs were imported. after a couple of years, there were fewer deer, but the average running speed of he deer had increased. this is an example of:

In a normal year, the bird will likely eat more brown grasshoppers bc they're easier to see. the green grasshoppers will survive and reproduce (more green in population). in a drought, the bird will eat more green than brown grasshoppers bc they're easier to see. brown grasshoppers will survive and reproduce (more brown in population).

a population of grasshoppers in the Kansas prairie has 2 color phenotypes, green and brown. Typically the prairie receives adequate water to maintain healthy green grass. Assume a bird that eats grasshoppers moves into the prairie. How will this affect the natural selection of grasshoppers? How might this change in a drought year?

founder effect and genetic drift

as world travel becomes easier and human populations intermix, the occurrence of what phenomenon will probably decrease? - sexual selection - mutation - founder effect and genetic drift - immigration

they are more likely to attract a mate

birds with extravagant plumage may be able to pass their genes to the next generation better than drab birds because:

genetic drift

chance events that change allele frequencies in small populations

variation- no difference in traits to select without it. species would not change or adapt too many individuals in a population to all survive- must choose between these individuals with the "best" traits since not all can survive competition for survival- important to differentiate which characteristics actually are the "best" for survival passing on beneficial traits for survival to offspring- important because it continues the process of evolution because passing along traits for survival spreads these traits throughout the population

Darwin is considered the "father of evolutionary biology." his theory of evolution by natural selection states that five simple factors must be present for evolution to occur. name four of the five factors and discuss the importance of each.

the more favorable forms survive and reproduce, but others do not

darwin and wallace both realized that most species produce many more offspring than is necessary to maintain a constant population. what is the fate of the excess individuals?

homologous = similar internal structures, different external structures (suggests evolutionary relationship) ex: bone structures in bats, alligators, humans analogous = similar external structures, different internal structures (does not suggest evolutionary relationship) ex: sugar gliders and flying squirrels

describe the difference between homologous and analogous structures in organisms, and give an example of each.

gene flow

elephants have a matriarchal society, and young males are driven out of the herd when they reach adulthood. from an evolutionary standpoint, what does this accomplish?

if they mate successfully and their offspring can also mate successfully, all are the same species.

fruit fly species all look more or less alike. if you have a male and female fruit fly, what would be the best way to determine that they are the same species?

homologous structures

homologous structures, such as a bat wing and a whale flipper, are/have:

hybrid infertility

hybrid organisms survive but do not produce fertile offspring. this is the definition of:

natural selection would not occur in that population

if a population consisted only of individuals cloned from a single organism, then:

if a mutation had previously occurred that caused white fur, such white squirrels would have a better chance to survive and reproduce

if the weather in Richmond, Virginia, changed to a very cold climate (snow on the ground 8 months of each year) over the next few years, what change might occur?

punctuated equilibrium

in the fossil record, species suddenly appear, remain more or less unchanged for varying periods of geologic time, and then disappear from the record. this trend best supports the theory of ____.

analogous

insect wings, bat wings, and the flaps of tissues between the limbs and body of "flying" squirrels are _______.

sympatric

interbreeding two different species of lovebirds produces offspring unable to build a nest after they mature because they lack the innate knowledge needed to carry the nesting materials. the hybrid offspring do not reproduce, and this limits genetic mixing of the two species. this is an example of ________ speciation

pests with resistant genes will survive and reproduce

many commercial pesticides become less effective after 2 to three years because:

are random

mutations ____ - are always beneficial - occur to solve problems for species (goal oriented) - are always detrimental - are random

the available food supply

natural selection adjusts the shape of the beaks among Darwin's finches in response to _______.

mechanical incompatibility

the Great Dane and Chihuahua are both domestic dogs, the same species. However, mating between them is limited by:

sexual

the fact that females tend to mate with brightly coloured males is an example of _____ selection

all the alleles for a particular trait in all the individuals in the population.

the gene pool for a particular gene is:

more they will differ in adaptations

the longer two populations are kept from interbreeding, the:

the lack of a mechanism to explain how traits were passed to offspring intact when most believed inheritance worked through blending

the major weakness of darwin's theory during his lifetime was:

behavioral isolation

the many species of tree frogs that inhabit forests in the eastern US maintain their genetic isolation from other species by several mechanisms, including "singing" slightly different songs. which type of isolating mechanism does this represent?

gene flow

the net migration of alleles into or out of a population from neighboring populations

the best-adapted individuals survive and reproduce, contributing the most genes to the next generation

the theory of natural selection states that:

allopatric

two populations of mountain-dwelling salamanders are separated by an impassable valley. the populations are:

adaptive radiation / divergent evolution

when a species invades a new habitat and evolves rapidly into several new species to better exploit new resources, what type of speciation has occurred?

a woman who lives 25 years and has 6 children

which example is favored in terms of natural selection? - a woman who lives 25 years and has 6 children - a woman who lives 105 years and has 2 children - a man who live 120 years and has no children - a woman who lives 35 years and has 4 children

populations evolve

which of the following statements about evolution is true? - populations evolve - evolution can proceed to a limited extent without the occurrence of mutation - evolution involves maintaining a constant frequency of alleles in the gene pool individuals evolve

temporal

Moss A produces gametes in May, and moss B produces gametes in June. this is an example of a(n) _____ isolating mechanism