bio chapter 16

genotypes

Assortative mating can cause the frequency of _____ to change within a population.

gene flow

A Canada goose leaving it's population in order to mate with a goose from another population is an example of _______ ________.

alleles

A gene pool includes all of the _________ of all of the genes of a species.

population

A group of organisms of a single species living in the same geographic area is called a

founder effect

A type of genetic drift in which a small number of individuals form a new population away from the original one is called the ______.

assortative

A type of mating that occurs when individuals choose a mate with a preferred trait is called ______ mating.

benefit cost

According to cost-benefit analysis, the ______ of partaking in a particular behavior or strategy must outweigh the ______.

genepool

All of the alleles of all of the genes in a population is known as the _______.

population

All of the western blue birds living in a 100 hectare forest would be an example of a(n) ______.

sickle cell disease

An abnormal form of hemoglobin causes

there is no reproductive isolation to prevent gene flow

British land snails are an example of disruptive selection. in the grassy fields, the light-banded snails escape bird predators. in the darker forest, the dark snails survive and the light-banded snails are eaten. the different colored snails have the opportunity to interact and breed across the British landscape. why doesn't this "disruptive selection" eventually lead to two separate species?

variation

During times of environmental change, populations with genetic ____________ have a better chance of adapting.

alleles

Gene flow causes microevolution by introducing new or rare_____ into a population.

bacterium

Gonorrhea is becoming more difficult to treat because antibiotic resistance is developing in the ______ that causes gonorrhea

Required to defend against predators. Requires a larger amount of food.

Identify the negatives of being a dominant baboon. required to mate with more females Required to defend against predators. Requires a larger amount of food.

6 katydids in an isolated prairie

Identify the population that has the greatest chance of becoming reproductively isolated over time. 6 katydids in an isolated prairie 7 elk living in one of several neighboring herds in Colorado 300 geese living on a pond

Imperfections are a compromise for beneficial traits.

Identify why certain traits are not perfect.

genetics

If a scientist studies the diversity of genes in a population they are studying population ______

polygenic

If a trait is controlled by more than one gene, the trait is referred to as being ______.

reproductively

If migration between populations does not occur, the gene pools of those populations may become different over time which can lead to the populations becoming ________ isolated.

access to mating

In examining male competition using cost-benefit analysis, the benefit that a male receives is in increased _____.

sexual dimorphism

In some animals the males and females differ in size and other characteristics. This is referred to as ______.

dominance

In some populations, high-ranking individuals have greater access to resources which cause males or females to establish ______ hierarchies

directional

Increases the frequency of an extreme form of a trait. The extreme phenotype is favored and the direction of the curve moves toward that phenotype during

100,000

It is estimated that a mutation occurs once in every _____ cell divisions.

disruptive selection

Maintains high levels of two different forms of a trait. The maintenance of two extreme phenotypes within a population in an environment that is subject to change results

monopolizing fertile females

Male baboons at the top of a dominance hierarchy benefit by _____.

genetic variation

Mutations serve as a source of new ___________ and are caused by changes to an organisms

adaptive

Natural selection favors the phenotype that is most _________.

Equilibrium

No mutations, no migration, random mating, no selection, and a large gene pool are required to maintain Hardy-Weinberg _______

gene

Population genetics studies the diversity of a population at the level of the ________.

dominance

Populations that have a structure in which higher-ranking animals have greater access to resources than lower-ranking animals are said to have _______ hierarchies.

malaria

Regions of Africa, in which populations have high frequencies of the sickle cell allele, will have high rates of _______ in their environments.

that females and males differ in size and other traits

Sexual dimorphism means ______.

compete selecting

Sexual selection in males usually results in an increased ability to _________ for mates, whereas sexual selection in females usually involves ___________ a mate with the best fitness.

hemoglobin

Sickle-cell disease is caused by an abnormal form of ____ in red blood cells.

false; it causes imperfect adaptation

T OR F: Most adaptations resulting from natural selection are perfectly suited to the environment.

false

T or F: a population of organisms that reproduce asexually will display more variation than a population that reproduces sexually

true

T or F: the founder effect is an example of genetic drift in which rare alleles occur at a higher frequency in a population isolated from the general population

true

T or F: you have been studying a newly discovered species of lemur. you have established that sexual selection has been a powerful force in the evolution of this species and it is clear that female choice plays an important role in determining which males procure mates. after many hours of observation and data collection, you find that females prefer males that are proficient at collecting sap and fruit. you should conclude that your data strongly supports the good genes hypothesis

defensive

Territoriality relates to ______ behaviors.

resistance

The STD gonorrhea is becoming more difficult to treat due to the development of antibiotic

sexual

The adaptive changes in males and females that lead to an increased ability to secure a mate is called ______ mating

Microevolution

The allele and genotype changes occurring within a population is known as __________.

mating behavior

The alleles in nonrandom mating assort according to ______.

territory

The area that is defended against competitors is called a

natural disaster

The bottleneck effect is the loss of genetic diversity that can be caused by ______.

territoriality

The defensive behavior necessary to defend a territory is called

homozygous

The heterozygote advantage means that the heterozygote for a trait has an advantage over the two

stabilizing selection

The heterozygote advantage regarding sickle-cell disease is an example of

runaway

The hypothesis regarding sexual selection that states that females choose mates on the basis of appearance is called the _____ hypothesis.

good genes

The hypothesis regarding sexual selection that states that females choose mates on the basis of traits that increase a male's chance of survival is called the _____ hypothesis.

heterozygous

The maintenance of genetic diversity of future generations is often maintained through the _______ advantage

Because female peacocks choose to mate with males that have these ornate tails.

The peacock's tail is bright and showy and makes the male prone to predation. Why has natural selection not eliminated this trait from the population?

frequency

The percentage of each allele in a population's gene pool is referred to as an allele

mutations

The raw material for evolutionary change, which introduces new variations among members of a population is caused by _______.

it increases the populations chances of survival in changing environmental conditions.

Variation within a population is important because

frequency of the dominant allele

What does p represent in the Hardy-Weinberg principle?

frequencies will change

What will happen to the genotype frequencies of a population if assortative mating takes place?

genetic drift

When chance causes only certain members of a population to reproduce and pass on their alleles to the next generation it is called _____

non random

When individuals mate based upon preferences it is known as _____ mating

Hh

Which allele combination represents the heterozygote advantage? help maintain genetic diversity

typhoid fever

Which disease is associated with cystic fibrosis and thought to have kept the recessive allele within the population?

p2 + 2pq + q2

Which equation describes the genotype frequencies of a non-evolving population?

HbAHbS

Which genotype is most prevalent in regions of Africa that have high rates of malaria? have an advantage in environment where malaria is present

no selection no new members can join the population and no existing members can leave no mutation no genetic drift

Which of the following are conditions that a population must meet in order to maintain Hardy-Weinberg principle?

founder effect bottleneck effect

Which of the following are types of genetic drift?

disruptive

Which type of selection is most likely to persist in an environment that is subject to a high degree of change?

the percentage of each allele in a population

allele frequency is.....

directional

at the beginning of a research project on egg laying in seagulls, a researcher noted that the birds laid an average of 7.9 eggs per cloth. after studying the population for 15 generations, the researcher noted that the birds were now laying 3-4 eggs per clutch. What type of natural selection is occurring in the population of gulls

the founder effect

if the small groups of Viking explorers in Greenland and North America had survived and given rise to new populations, such a scenario would be an example of

have similar gene pools

if there is gene flow between 2 adjacent populations of the same species, then the 2 populations will

is evolution did not occur

in a population, the allele frequency for red flower color remained at 0.7 and the allele frequency for white flower at 0.3 for 6 generations. this ________ an example of a Hardy- Weinberg equilibrium in that _________

stabilizing

increases the frequency of an intermediate form of a trait. A selection type that has a large peak in the center of the range of distribution

bottleneck effect

the northern elephant seal was hunted almost to extinction during the 18th and 19th centuries. less than 100 seals were left to contribute to the gene pool of their future generations. since the early 20th century, the elephant seals have been protected by laws in both US and Mexico. over 100000 seals now inhabit western shores of North America, all related to the small population that survived the slaughter of hunters. scientists fear the elephants seals may be more susceptible to disease and pollution due to

heterozygous advantage

the recessive alleles for sickle cell anemia are more prevalent in regions of Africa where malaria is prevalent than it is in regions where there is no malaria. this is due to

mutation genetic recombination due to fertilization gene flow

variance within a population is maintained by

mutation

what condition is not necessary to maintain Hardy-Weinberg theory? -no selection -mutation -no migration -random mating

gene flow

the movement of alleles between populations.

directional selection occurs when one extreme phenotype in a population is favored disruptive selection favors 2 extreme phenotypes

what statements about natural selection are true? -directional selection occurs when one extreme phenotype in a population is favored -stabilizing selection favors all phenotypes equally -disruptive selection favors 2 extreme phenotypes -directional selection is most common in stable environments

small population (you need a large population)

which condition is not among the requirements of Hardy-Weinberg equilibrium? -random mating -no selection of phenotype -small population -no net mutations

random mating

which of the following conditions is necessary to maintain the Hardy-Weinberg equilibrium? random mating gene flow genetic drift mutations

all choices are correct

which of the following is required for natural selection to occur in a population? heritable variation accumulation of adaptive traits differential reproduction all choices are correct

it may lead to an allele becoming fixed in a population

which of the following is true about genetic drift? -it is more likely to occur in a large population than in a small population -it may lead to an allele becoming fixed in a population -it increases the number of heterozygous in a population -it increases the frequency of rare alleles in a population

mutagens

Chemical or physical agents that cause mutation are called

at any time, even where when bacteria are not exposed to the drug

mutations that result in resistance to specific antibiotics in bacterial organisms occur

All of the choices are correct

which of the following likely reflects the presence of one or more gene mutations? -fruit flies subjected to intense radiation produce a wider array of variable offspring -a chemical leaking from the surface of an old abandoned coal mine alters a regulatory gene so that a cricket nymph develops an extra set of eyes -the bacteria that causes gonorrhea, a common sexually transmitted disease, have previously been killed by penicillin; however, after continuous usage of the antibiotic, penicillin-resistant strains are now prevalent -radiation causes an alteration in a DNA nucleotide sequence, which is discovered when mapped, but which appears to be neither increasing nor decreasing in successive generations -all of the choices are correct

graph with a single tall and narrow peak located in the center a graph indicating gray guinea pigs have an advantage over black guinea pigs and white guinea pigs

you have done extensive research for 30 years on the frequency of coat colors (black, grey, white) in a guinea pig population located in the Andes Mountains. you suspect that your guinea pig population is undergoing stabilizing selection. if this is the case, what would you expect to find when you graph your data?