Biology II - Chapter 13: How Populations Evolve

Human populations are much more mobile than 300 years ago. What is one consequence of this? - The bottleneck effect is a more important cause of microevolution than in the past. - genetic drift is a less important cause of microevolution than in the past. - Gene flow is a more important cause of microevolution in the past. - Gene flow is a less important cause of microevolution than in the past. - the founder effect is a more important cause of microevolution than in the past.

Gene flow is a more important cause of microevolution in the past.

The frequency of alleles in a population should remain constant unless there are other factors at work. This principle is known as the _____.

Hardy-Weinberg Principle

Briefly explain how a heterozygous individual "protects" the recessive allele from elimination within a population.

It is always present in the genes and can continue to be passed down. However, it is not expressed.

list and describe the 5 conditions that must be met to remain in Hardy-Weinberg Equilibrium

Large population: large population limits chance fluctuation. No gene flow: individuals moving into or out of populations add or remove alleles from the gene pool. no mutations: mutations modify the gene pool by changing alleles or removing them. Random mating: random mating ensures mixing of the alleles. No natural selection: this can alter allele frequencies through the unequal reproductive success created by natural selection.

Briefly explain how mutation allows for variation achieved by sexual reproduction.

Mutations create genetic diversity. These mutations, if it occurs in gametes, can be passed on to offspring.

Which of the following is a misconception regarding natural selection? - Natural selection progressively refines organisms' adaptations, eventually leading to perfection. - Natural selection can only act to diminish or amplify heritable traits. - There is a struggle for existence among individuals because organisms tend to produce far more offspring than the environment can support. - Individuals do not evolve; populations do.

Natural selection progressively refines organisms' adaptations, eventually leading to perfection.

Would a jellyfish be likely to leave behind a fossil? Briefly explain your answer.

No, a jellyfish does not have bones that would leave behind a fossil. They are made of soft tissues.

T/F: Evolutionary trees show patterns of descent and are supported by homologous structures.

True

T/F: The bones and teeth of organisms are capable of not decaying and often become fossils.

True

What is meant by the following statement? Population has a "shallow" gene pool.

a population is a group of a certain species living in a certain area during a certain time. Therefore, the diversity of genes would be low because all the organisms are sharing their genes with only others within the population.

A scientist is doing a field study in the Mojave Desert. She observes a type of rabbit that has very large and wide ears loaded with blood vessels. She hypothesizes that the large surface area of the ears aids in heat dissipation, thus cooling the rabbit off. What would the specialized ears of this rabbit be considered?

adaptation

This unequal reproduction in a population leads to the gradual accumulation of ________ to the environment.

adaptations

A(n) ___ is an alternative version of a gene.

allele

Darwin used the practice of ______________ to gain insight into his ideas about a mechanism for descent with modification

artificial selection

Which of the following can be passed on to offspring from their parents? - muscles from body building - a tattoo - a deep tan from constant tanning - blonde hair

blonde hair

It is possible for mutation, genetic drift, and gene flow to cause microevolution. However, only by a(n) ______ event could they lead to that population of organisms becoming better adapted to their environment.

chance

In evolutionary terms, an organism's relative fitness is measured by its __________. - ability to avoid passing on mutations in its genome to the next generation more effectively than other individuals in the population - ability to adapt to sudden changes in the environment relative to the ability of other individuals to adapt to those same changes - contribution to the gene pool of the next generation relative to the contribution of other organisms to that gene pool - ability to attract the most fertile mates and mate with them, relative to other members of the population - strength and hardiness relative to other individuals in the population

contribution to the gene pool of the next generation relative to the contribution of other organisms to that gene pool

The similarities among all living things in their DNA, RNA and genetic code provide strong evidence for which of the following? - descent from several ancestors - evolution of homologous anatomical structures - descent from a very distant common ancestor - similar structures have different functions in different organisms - the effects of artificial selection over millions of years

descent from a very distant common ancestor

a classic example of microevolution is the shift in a population of moths from light colored to dark colored during the industrial revolution in England. This shift in moth color was brought about by an accumulation of soot on the trees and other vegetation around the factories of the cities. This is an example of what type of selection?

directional

T/F: Catfish living in two different rivers would be considered members of the same population.

false

T/F: The 3 main agents of evolutionary change are: natural selection, genetic drift, and nonrandom mating.

false (natural selection, genetic drift, and gene flow)

the evolution of populations due to chance is __.

genetic drift

An inactive pseudogene that normally encodes for the enzyme GLO results in which of the following? - humans must consume vitamin D in their diet. - animals can manufacture vitamin C. - humans must consume vitamin C in their diet. - humans can manufacture vitamin C. - most mammals can manufacture vitamin C.

humans must consume vitamin C in their diet.

An examination of the sedimentary rock at the Grand Canyon allows scientists to observe fossils that are ____ years old. - hundreds of - 6,000 - Thousands of - hundreds of millions of - 100,000

hundreds of millions of

Two key observations underlying natural selection are that members of a population vary in their _____ and that all species can produce more offspring than the environment can support.

inherited traits

Changes in allele frequencies in a population over time is ____.

microevolution

a population of bacteria sees an increase in the number of bacteria resistant to a certain antibiotic over a number of generations. This is known as ______.

microevolution

The phrase Darwin used to describe his broad theory of evolution is ''descent with ____.

modification

A(n) __ is a change in the nucleotide sequence of DNA.

mutation

A population of bacteria contains no members with resistance to penicillin. Several generations pass with the bacteria reproducing. A researcher adds penicillin to the population of bacteria and discovers a few bacteria remain after the application of the antibiotic. Assume no new bacteria were introduced to the population. What can explain this?

mutation occurred in one or more of the bacteria, being able to resist the antibiotic.

New alleles arise by __________, which causes __________. - mutation: cellular damage - adaptation: improved fitness - mutation: genetic variation - natural selection: genetic variation - natural selection: cellular damage

mutation: genetic variation

Darwin inferred that those organisms with traits best suited to the environment tend to leave more ________ than other members of a population.

offspring

people have the misconception that pesticide resistance in insects and antibiotic resistance in bacteria are examples of artificial selection and not natural selection. briefly explain why they are examples of natural selection.

people are not actively choosing to make bacteria and insects more problematic. bacteria and insects grow immunity overtime due to environmental factors of antibiotics or pesticides.

What are the consequences for a population of balancing selection and heterozygote advantage? - preserve genetic variation - favor intermediate phenotypes - allow artificial selection to work - favor extreme phenotypes - reduce genetic variation

preserve genetic variation

Which of the following choices lists conditions that favor the development of drug resistance in bacteria? - nonrandom mutation and random selection - random mutation and nonrandom selection - random mutation and random selection - nonrandom mutation and nonrandom selection - random mutation and stabilizing selection

random mutation and nonrandom selection

The plumage of peacocks is an example of ______.

sexual dimorphism

What kind of sexual selection is demonstrated when the peahen selects her mate?

sexual selection

What do all organisms after point 2 have in common? Refer to figure 13.5 in the textbook.

tetrapod limbs

Which of the following best describes relative fitness? - the creation of new gene combinations - individuals migrating into and out of an area - the ability to produce healthy offspring - the change in a population's gene pool over generations

the ability to produce healthy offspring

Charles Darwin reasoned that fossils must exist that link two seemingly very different types of organisms. These fossils are termed ____.

transitional forms

all of life is related through common ancestry, accounting for the ___ of life.

unity

list 3 key points about evolution by natural selection

1.Individuals do not evolve; populations do. 2. Natural selection works only on heritable traits. 3. There is no overall directed goal of natural selection.

Long ago, rats were common inhabitants of ocean-going ships. Imagine that rats from one town in Norway hitched rides on three different ships. Ten years later, most rats on the Ninã were brown; on the Pinta, black; and on the Santa Maria, white. This reveals the effects of which specific mechanism of microevolution? - gene flow - mutation - founder effect - bottleneck effect - survival of the fittest

founder effect

Which of the following are reasons why natural selection cannot fashion "perfect" organisms? - Natural selection often creates mutations. - Evolution is limited by historical constraints. - Adaptations are often compromises. - Change, natural selection, and the environment all interact.

- Evolution is limited by historical constraints. - Adaptations are often compromises. - Change, natural selection, and the environment all interact.

List 3 components of sexual reproduction that account for genetic variation.

- crossing over - independent assortment of chromosomes - random fertilization

What are the main purposes of the evolutionary tree shown in the video? - The tree outlines the evolutionary relationships among groups of tetrapods. - The tree shows that the ancestors of crocodiles had feathers. - The tree shows that lungfishes gave rise to tetrapods. - The tree highlights some homologous traits shared by different groups of tetrapods.

- the tree outlines the evolutionary relationships among groups of tetrapods. - the tree highlights some homologous traits shared by different groups of tetrapods.

list the reasons why natural selection does not create perfect organisms.

1. only works with alleles that are present 2. evolution is limited by historical constraints 3. adaptations are usually compromises 4. chance, natural selection and the environment all interact.

list 3 ways in which human practices are contributing to the creation of antibiotic resistant strains of bacteria.

1. over prescription 2. stopping prescription before dosage is complete 3. antibiotics used by ranchers in cattle

For most plants and animals, the mutation rate is about __________ genes per generation. In which type of populations will the mutation rate have the least impact? - 1/10,000: populations of organisms that are haploid. - 1/10,000,000: populations that use asexual reproduction - 1/100,000: populations with long time spans between generations - 1/10,000: populations of organisms that are diploid - 1/10,000: populations with short time spans between generations

1/100,000: populations with long time spans between generations

Which of the following states the differences between artificial selection and natural selection? - Artificial selection takes place over a relatively short number of generations: natural selection requires a great number of generations. - Artificial selection works only on heritable traits: natural selection works on either acquired or heritable traits. - Artificial selection is not goal-directed: natural selection is goal-directed in that it allows survival of only the fittest members of the species. - Artificial selection allows entire populations, such as dog breeds, to evolve natural selection favors individual survival. - Artificial selection concerns itself mainly with animal species: natural selection works on all species.

Artificial selection takes place over a relatively short number of generations: natural selection requires a great number of generations.

Compare and Contrast artificial and natural selections

Artificial: Humans select for an advantageous trait and then selectively breed those organisms for it. Natural: Environmental conditions present in an organism's area select for advantageous traits, which are passed on to offspring when that organism reproduces Both: Both lead to changes in a population's traits over time.

The famous biologist who is considered the father of evolution is ____.

Charles Darwin

All organisms, from humans to bacteria, use DNA as their molecule of heredity. What conclusion can be drawn from this observation?

Everything evolved from a common ancestor

An argument against evolution by natural selection is that it is not observable on a human time scale. However, this is not exactly true. List two examples of evolution by natural selection that have been documented.

Evolution is examined in insects becoming resistant to pesticides and bacteria becoming resistant to antibiotics.

What would be true regarding any fossils found in strata at the top versus fossils found in lower strata?

Fossils at the top of the strata are newer (younger) than those at the bottom.

compare and contrast heterozygote advantages and frequency dependent selection

Heterozygote advantages: Where the heterozygote individual has greater reproductive success than either homozygote frequency dependent selection: Maintains phenotypes in a population around 50% by acting on either phenotype if it becomes too common. both: Both maintain genetic variation within in a population

Which would be a good example of intrasexual selection? - Male elk suffer heavy wolf predation because of their large antlers, producing selection against increased antler size in the population. - Bright-colored male bluebirds are more attractive to mates than dull-colored individuals. - Male elephant seals use their huge bodies to batter each other in battles for access to mates. - Female birds discriminate among potential mates and choose their partners based on the quality of the song

Male elephant seals use their huge bodies to batter each other in battles for access to mates.

Which statement reflects a possible weakness of the fossil record? - Only large animals can be fossilized. - Many species probably did not die in the right place at the right time to be captured in fossils, and many fossils will never by found by paleontologists. - The fossil record cannot answer any questions about behavior. - The fossil record does not indicate chronology (the sequence of events).

Many species probably did not die in the right place at the right time to be captured in fossils, and many fossils will never by found by paleontologists.

a population of dogs has two different coat colors coded for by two different alleles. The character of coat color follows Mendel's rules. The frequency of one of the alleles for coat color is 250/1150. What is the frequency of both alleles in the population of dogs? What is the population of dogs?

Population 575 (1150 alleles) frequencies are .22 and .78

while on his voyage, Darwin made many specific observations and was influenced by many factors that aided him in his thinking about evolution. List two specific observations or factors that influenced Darwin during his voyage.

Principles of Geology by Charles Lyell and an earthquake occurring in Chile

Which of the following statements about how Darwin analyzed his results from his Beagle voyage is incorrect? - Darwin observed that organisms living near each other were more similar than those living in similar but distant environment. - Darwin was influenced by other publications during his time. - Although it was a sea voyage, most of Darwin's time was spent on land. - Soon after his return, he published The Origin of Species, his most important work. - Darwin focused primarily on plants and animals along the coast of South America.

Soon after his return, he published The Origin of Species, his most important work.

describe and give an example of the 3 ways natural selection can alter a population's phenotypes.

Stabilizing selection: favors the intermediate phenotypes, reduces variation and maintains an intermediate trait Example: human birth weight Directional selection: shifts the population by acting against one of the extreme phenotypes Example: bacteria exposed to an antibiotic Disruptive selection: conditions exist that favor both extreme phenotypes and not intermediate. Example: small and large billed birds find small and large seeds while medium bill sized birds cannot find food.

Among antibiotic-resistant bacteria, __________ causes the highest number of infections, while __________ causes the greatest proportion of cases classified as "urgent" by the Centers for Disease Control and Prevention. - Salmonella: Neisseria gonorrhea - Neisseria gonorrhea: Campylobacter - Salmonella: Streptococcus pneumoniae - Streptococcus pneumoniae: Neisseria gonorrhea - Streptococcus pneumoniae: Campylobacter

Streptococcus pneumoniae: Neisseria gonorrhea

In intersexual selection, individuals of one sex are often choosy in selecting their mates. Which of these reported outcomes from experiments with birds and frogs support the hypothesis that females prefer male traits that are correlated with "good genes?" - Females who mated with more attractive males were more effective mothers than females who mated with less attractive males. - Females who mated with more attractive males were less effective mothers than females who mated with less attractive males. - The offspring of more attractive males have better health and longer survival than the offspring of less attractive males. - The offspring of more attractive males have poorer health and shorter survival than the offspring of less attractive males. - The offspring of more attractive males are less numerous than the offspring of less attractive males.

The offspring of more attractive males have better health and longer survival than the offspring of less attractive males.

Barn swallows are found throughout North America. In Maine, two extremely cold winters in a row led to increased survival of birds with larger bodies than average. What type of selection was operating in this situation? - adaptive - directional - artificial - disruptive - stabilizing

directional

The __ of life arises from the adaptation of species to different habitats over long spans of time.

diversity

Which of the following is the definition of a fossil cast? - entire organisms that are preserved in material such as amber or ice - empty molds of specimens left in sediment that are filled in with dissolved minerals - specimens that were "cast" far away from their original habitat - the hard parts of animals, such as bones, that are rich in minerals - the tibia or other leg bones of a large animal left in fine-grained sand or mud

empty molds of specimens left in sediment that are filled in with dissolved minerals.

a few persons go boating in the boundary waters of minnesota. they pulled their own boat to and from their campsite, without their knowledge, a small population of aquatic organisms is in/on the boat. as soon as they get home, they put their boat back in the pond behind the house. there are no other members of this species in the pond. what mechanism is this?

founder effect

Which of the following states the Hardy-Weinberg equation in English? - the frequency of heterozygotes plus the frequency of homozygous dominants minus the frequency of heterozygotes equals one - the frequency of homozygous dominants plus the frequency of homozygous recessives equals one. - the frequency of homozygous dominants plus the frequency of heterozygotes plus the frequency of homozygous recessive equals one hundred percent. - frequency of homozygous dominants plus the frequency of heterozygotes plus the frequency of homozygous recessives equals one. - the frequency of homozygous dominants squared plus two times the frequency of heterozygotes plus the frequency of homozygous recessives squared equals one.

frequency of homozygous dominants plus the frequency of heterozygotes plus the frequency of homozygous recessives equals one.

The total collection of alleles in a population at a given time is the population's _____.

gene pool

Which of the following is a true statement about Charles Darwin? - He proposed natural selection as the mechanism of evolution. - He worked out the principles of population genetics. - He was the first to discover that living things can change or evolve. - He based his theory on the inheritance of acquired characteristics

he proposed natural selection as a mechanism of evolution

A cat's forelimb and a human's forelimb are examples of _______.

homologous structures

The similarities seen in certain species that result from common ancestry is known as _____.

homology

Which of the following most accurately and directly measures an organism's relative fitness? - how successful it is when pitted against others in contests of strength or endurance - its mutation rate - how many fertile offspring it produces - its ability to withstand environmental extremes

how many fertile offspring it produces

Scientists regard Darwin's concept of evolution by means of natural selection as a theory. Which of the following accurately describes characteristics of a scientific theory? - it generates new hypotheses. it is a widely accepted explanatory idea that is broader in scope than a hypothesis. - it is believed by most people of its time. - it is supported by a large body of evidence.

it generates new hypotheses. it is a widely accepted explanatory idea that is broader in scope than a hypothesis. - it is supported by a large body of evidence.

Ambulocetus, whose name means "walking whale," was a transitional species between modern whales and their ancestors. Which choice includes (1) characteristic that would have equipped Ambulocetus to function well on land and (2) characteristic that would have equipped it to function well in water? - large pelvis (land): powerful tail and joints of forelimbs (water) - joints of forelimbs (land): powerful tail and large, paddle-like hind feet (water) - tiny forelimbs (land): powerful tail, and large, paddle-like hind feet (water) - joints of forelimbs (land): large pelvic bones and tiny hind feet (water) - large pelvis (land): small tail and large, paddle-like hind feet (water)

joints of forelimbs (land): powerful tail and large, paddle-like hind feet (water)

Darwin proposed a mechanism for how evolution occurs, which he called ____.

natural selection

describe and give an example for the 3 main agents of evolutionary change

natural selection: ability for some organisms to leave more offspring than others due to some traits. example: a cactus developing needles over time to protect itself from animals genetic drift: chance events happening and changing the frequency of alleles. Example: a forest fire wiping out a national forest and creates a bottleneck effect on populations Gene flow: when individuals move in or out of a population. Example: prairie chickens being taken from one state and placed in a population with the Illinois Prairie Chickens

A man wins the National Bodybuilding Association's Man of the Year award. However, he never has any children due to a personal choice. What is his relative fitness within the population? Briefly explain your answer.

none, he has no kids

A(n) ____ is a group of individuals of the same species living in the same area that interact with each other.

population

Which condition would disturb the Hardy-Weinberg equilibrium and cause the gene pool to change? - No mutations occur. - All genotypes on average produce an equal number of fertile adult offspring. - Mating occurs at random. - Several homozygous recessive individuals leave the population.

several homozygous recessive individuals leave the population.

Which of the following initial conditions must be true in order for a population of insects to become resistant to a new pesticide? - some members of the population must become genetically resistant to the pesticide. - most members of the population must be genetically resistant to the pesticide. - no members of the population must be genetically resistant to the pesticide. - all members of the population must be genetically resistant to the pesticide. - some members of the population must be genetically resistant to the pesticide.

some members of the population must be genetically resistant to the pesticide.

Peter and Rosemary Grant researched beak size in finches in the Galápagos Islands. What did their work show? - the effects of DDT on survival of finches. - that natural selection is an ongoing, constant process. - that evolution occurs over a very long time course. - the effects of global warming on nesting patterns. - the effects of habitat destruction on the gene pool.

that natural selection is an ongoing, constant process

The habitat of the greater prairie chicken was devastated by farming and other human activities in the 19th and 20th centuries. These bird populations experienced __________, which __________ their number of alleles. - the bottleneck effect, reduced - the founder effect, reduced - the bottleneck effect, increased - stabilizing selection, reduced - natural selection, altered

the bottleneck effect, reduced

Which of the following is a true statement about homologous structures in two different organisms? - They perform the same function regardless of structural similarity or difference. - the show that the organisms evolved from different ancestral lines. - they are structurally similar but have different functions. - they are structurally different but have similar functions. - they appeared at about the same time in evolution.

they are structurally similar but have different functions

Which of the following is a typical use of the Hardy-Weinberg equation in public health? - to help determine the best treatments for particular diseases - to diagnose particular diseases in individuals - to estimate the number of survivors of particular serious diseases - to predict the likely course of particular diseases - to estimate the number of people with alleles for specific diseases

to estimate the number of people with alleles for specific diseases

Which of the following is a typical use of the Hardy-Weinberg equation in public health? - to diagnose particular diseases in individuals. - to predict the likely course of particular diseases. - to estimate the number of people with alleles for specific diseases. - to help determine the best treatments for particular diseases. - to estimate the number of survivors of particular serious diseases.

to estimate the number of people with alleles for specific diseases.

T/F: Natural selection can alter the variation of phenotypes within a population in 3 ways.

true