Bio. Final

Mendel was a careful researcher who studied the inheritance of certain traits in garden peas. What are some of the research practices Mendel used?

a. He crossed true-breeding pea plants.

b. He allowed eggs to be fertilized only by self-pollination.

c. He analyzed his data mathematically.

d. He controlled variables by studying one or two traits at a time.

d. He controlled variables by studying one or two traits at a time.

Mendel studied 7 traits in pea plants. One of the monohybrid crosses he made was between plants with round seeds (R) and plants with wrinkled seeds (r)

What was a conclusion that Mendel drew from the F2 generation?

a. Three fourths of the F2 plants show the round seed phenotype and carry the dominant allele for roundness.

b. One fourth of the F2 plants show the round seed phenotype and are heterozygous.

c. The F2 plants are all heterozygous.

d. The F2 plants all have wrinkled seeds, but some carry the allele for round seeds.

a. Three fourths of the F2 plants sow the round seed phenotype and carry the dominant allele for roundness.

A geneticist crossed tall pea plants and obtained 971 tall pea plants and 315 short pea plants in the f1 gen.

What were the genotypes of the parents that produced the offspring in the Punnett square shown, if T is the allele for tall, and t is the allele for short?

a. Tt

b. TT

c. tt

d. TtTt

a. Tt

The Punnett square describes the potential offspring of a cross. What phenotypes will be shown by the offspring?

a. All offspring will show the recessive phenotype for this trait.

b. All offspring will show the dominant phenotype for this trait.

c. Half of the offspring will show the dominant phenotype and half will show the recessive phenotype.

d. Three fourths of the offspring will show the dominant phenotype and one fourth will show the recessive phenotype.

b. All offspring will show the dominant phenotype for this trait

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Wolbachia pipentis is a species of bacteria that infect fruit flies. When the genome of the fruit fly was sequenced, it was found that most of the genome of the bacteria had been integrated into the fruit fly genome.

a. This passing of genes between organisms of different species is caused by mutations. This type of gene transfer can increase genetic variation only, if it happens in the cells that produce eggs and sperm.

b. This passing of genes between organisms of different species is called gene recombination and happens during sexual reproduction. This type of gene transfer has no effect on genetic variation.

c. This passing of genes between organisms of different species is caused by gene duplications. This type of gene transfer can increase genetic variation, if the duplicated genes acquire new functions.

d. This passing of genes between organisms of different species is called lateral gene transfer. This type of gene transfer can increase genetic variation, and therefore diversity.

d. This passing of genes between organisms of different species is called lateral gene transfer. This type of gene transfer can increase genetic variation, and therefore diversity.

Fifteen iguanas survived a hurricane on a raft of uprooted trees. After a month at sea, they colonized an island. They were the first of their species to arrive there. Evolutionary biologists predict that this group of iguanas could become a new species.

a. The island iguanas fill exactly the same niche on the island as they did before.

b. The island iguanas are geographically isolated from the original population.

c. The island iguanas evolve through favorable adaptations and natural selection.

d. The island iguanas have more genetic variation than the original population.

b. The island iguanas are geographically isolated from the original population

Robins typically lay four eggs. Four eggs allow the offspring to be well fed, whereas larger clutches may result in malnourished chicks that have a lower chance of survival. Fewer than four eggs per clutch may result in no surviving offspring if the eggs are preyed upon. Which pattern of natural selection most likely acts to keep four eggs the most common clutch size?

a. stabilizing selection

b. directional selection

c. disruptive selection

d. normal selection

a. Stabilizing selection

Do fossils provide a complete record of all the extinct species that lived on Earth? Why or why not?

a. Yes, because all species left fossils behind.

b. Yes, because the traits of many species can be inferred from a single fossil.

c. No, because many species went extinct without leaving fossils behind.

d. No, because fossils break apart after about 65 million years.

c. No, because many species went extinct without leaving fossils behind.

Scientists before Darwin had proposed that living things could change over time. Why was Darwin's theory of evolution more powerful and useful than the proposals of the other scientists?

a. Darwin explained the mechanism by which evolution occurred.

b. Darwin cited examples from nature that were based on observations.

c. Darwin used logical reasoning to argue that living things could change.

d. Darwin hypothesized that evidence from DNA and genes would explain how evolution occurs.

a. Darwin explained the mechanism by which evolution occurred.

Darwin collected and studied a variety of fossils. The fossils provided clues to ancient organisms. As Darwin concluded, how did ancient organisms compare to modern species?

a. The ancient organisms were identical to modern species.

b. The ancient organisms were larger or smaller than modern species, but otherwise identical.

c. The ancient organisms were similar to modern species, but differed in several ways.

d. The ancient organisms were very different from modern species, and lacked any significant similarities.

c. The ancient organisms were similar to modern species, but differed in several ways.

Artificial selection has produced a wide variety of crop plants, livestock, and pets. Which characteristic of artificial selection makes it different from natural selection?

a. Humans, not the environment, select which organisms survive and reproduce.

b. Adaptations develop gradually over many generations.

c. The stock that are reproduced are genetically identical.

d. All offspring are allowed to survive and reproduce.

a. Humans, not the environment, select which organisms survive and reproduce.

The adaptations of a pelican include its long, pouch-like beak. Why is the beak of the pelican an example of an adaptation?

a. The beak is a unique feature that is found only in pelicans.

b. All birds have beaks, but the beaks vary among different species.

c. The shape and structure of the beak have remained the same over many generations.

d. The shape and structure of the beak are inherited and help the pelican survive in its environment.

d. The shape and structure of the beak are inherited and help the pelican survive in its environment.

A variety of plants and animals live in a meadow ecosystem. According to Darwin's ideas about evolution, which of these meadow organisms has the greatest fitness?

a. a snake that eats many mice, and then is eaten by a hawk

b. a large, healthy hawk that does not find a mate

c. a female mouse that has many offspring

d. a lone tree that grows in the middle of the meadow

c. A female mouse that has many offspring

Edwin is studying a population of rabbits in the neighborhood that surrounds his home. He observes a variety of fur colors among the rabbits, including gray, white, and brown. The rabbit fur also has a variety of markings, including spots and bands.

Edwin argues that natural selection will occur on the rabbit population. It will result in a change in the distribution of fur colors and markings.

Which observation would provide the STRONGEST evidence in support of Edwin's argument?

a. Neighborhood plants can support a large increase in the rabbit population.

b. Fur color and markings do not affect the running speed of a rabbit.

c. A new predator tends to hunt more white rabbits than gray or brown rabbits.

d. Most of the rabbits are wildlife, while some are pets.

c. A new predator tends to hunt more white rabbits than gray or brown rabbits.

John states the following claim.

"Biogeography provides evidence for the theory of evolution."

To support this claim, which evidence would be MOST useful for John to cite?

a. A sequence of fossils shows that horses became smaller over time.

b. Polar bears and grizzly bears are similar in many ways, but are adapted to live in different regions.

c. Farm crops developed in Asia are now raised successfully in regions all over the world.

d. Fossils of plants and animals have been found on Antarctica, which now is covered in ice.

b. Polar bears and grizzly bears are similar in many ways, but are adapted to live in different regions.

A scientist argues that the hair of mammals and the feathers of birds are analogous structures. If the scientist is correct, what is the evolutionary relationship between hair and feathers?

a. Either hair evolved from feathers, or feathers evolved from hair.

b. Both hair and feathers evolved from the same structure in a common ancestor of birds and mammals.

c. Hair evolved in mammals at the same time as feathers evolved in birds.

d. The evolution of hair in mammals occurred independently of the evolution of feathers in birds.

d. The evolution of hair in mammals occurred independently of the evolution of feathers in birds.

The wings of ostriches are examples of vestigial structures. The wings provide evidence for which of these evolutionary relationships?

a. A new bird species without wings will evolve from ostriches.

b. A new bird species that has useful wings will evolve from ostriches.

c. An ancestor of ostriches had useful wings.

d. An ancestor of ostriches had vestigial structures.

c. An ancestor of ostriches had useful wings.

Charles Darwin applied a wide variety of observations to help him develop his ideas about evolution. Which general statement describes several of the observations that Darwin made and considered, and later incorporated into his Theory of Evolution?

a. Species may vary from place to place, but most species are distributed widely on all continents.

b. Fossils show that ancient species were identical or nearly identical to modern species.

c. All species use DNA to carry and translate genetic information.

d. Species on islands tend to resemble mainland species, yet differ from them in many ways.

d. Species on islands tend to resemble mainland species, yet differ from them in many ways.

A population of male and female goats is stranded on a large island. The goats differ from one another in several ways, including fur color, ear shape, and preferred food.

A scientist predicts that the average ear shape of the goats will change gradually over time. According to Darwin's ideas about evolution and natural selection, the accuracy of the prediction depends on which of these conditions?

a. Certain ear shapes allow the goats to hear a wider variety of sounds.

b. Certain ear shapes help the goats survive and reproduce on the island.

c. The island provides enough food to support an increase in the goat population.

d. The island lacks natural predators of goats.

b. Certain ear shapes help the goats survive and reproduce on the island.

Giraffes, camels, and horses share some traits, although they vary in other traits. Which statement accurately describes the evolution of these species?

a. Each species descended from an ancient common ancestor.

b. All three species evolved from three unrelated ancient ancestors.

c. Each species evolved uniquely, without any ancestors.

d. Two of the species descended from the other species.

a. Each species descended from an ancient common ancestor.

Brianna is mapping trees in a section of land. She observes that some of the trees are clumped together, some are uniformly separated, and some appear to be spaced randomly. What is she describing?

a. the population density

b. the population distribution

c. the population growth

d. the population outline

b. The population distribution

Murray is observing a bacterial colony that is growing in agar in a Petri dish. Agar is processed seaweed. Murray calculates that the population doubles in size every 32 hours.

Which conclusion is supported by Murray's observations?

a. The agar and air in the Petri dish are providing all of the resources needed by the bacteria.

b. The bacterial colony is growing in all regions of the agar in the Petri dish.

c. The bacterial colony will continue doubling in size indefinitely.

d. The agar and air in the Petri dish are limiting factors on the growth of the bacterial colony.

a. The agar and air in the Petri dish are providing all of the resources needed by the bacteria.

Walleyes and northern pike are both species of fish that live in freshwater lakes. Many lakes maintain large, healthy populations of both of these fish species year after year. Which statement about walleyes and northern pike is most useful in explaining how they are able to live together in the same habitat?

a. The two species are adapted to eat different types of food.

b. The two species are adapted to eat the same types of food.

c. The two species have different ranges of tolerance to oxygen content in water.

d. The two species have different ranges of tolerance to temperature.

a. The two species are adapted to eat different types of food.

Termites are able to digest wood because of microbes that live in their gut. The relationship between a termite and the microbes inside it is an example of what type of symbiosis?

a. parasitism

b. mutualism

c. commensalism

d. a predator-prey relationship

b. Mutualism

Thomas is describing an example of secondary succession. Which of the following events is most useful for him to include?

a. Lichens begin growing on rocks that formed from a volcanic eruption.

b. Many fishes die in a pond when oxygen levels decrease.

c. The populations of wolves and rabbits change in a cyclical pattern.

d. Small plants and animals return to the land after a forest fire.

d. Small plants and animals return to the land after a forest fire.

Barbara is studying the process of ecological succession in a temperate forest ecosystem. Her goal is to construct an explanation based on evidence. Observations of which of the following locations is most likely to provide useful evidence for Barbara to cite?

a. a healthy, undisturbed temperate forest ecosystem

b. a healthy temperate forest ecosystem a few years after a wildfire

c. a farmer's field that had been cleared from a temperate forest

d. a temperate forest that is changing due to invasive vines

b. A healthy temperate forest ecosystem a few years after a wildfire

The diagram shows an example of ecological succession.

Cleared soil → grasses → shrubs → softwood trees → hardwood trees

What can be inferred about the mature forest shown in the diagram?

a. It is an intermediate community that will begin primary succession.

b. It is an intermediate community that will give rise to new communities.

c. It is the climax community that will never change after it forms.

d. It is the climax community that is the last community of the succession process.

d. It is the climax community that is the last community of the succession process.

Scientists have observed that all cheetahs have very similar body structures, markings, and other physical traits. These observations provide evidence for which conclusion?

a. Cheetahs have low genetic diversity.

b. Cheetahs have low species diversity.

c. Cheetahs have high genetic diversity.

d. Cheetahs are minimally affected by biodiversity.

a. Cheetahs have low genetic diversity.

Carla claims that a strain of rose bushes is resilient to temperatures as low as 5°C. Which statement about rose bushes of this strain can be inferred from Carla's claim?

a. They grow better at 5°C than at higher temperatures.

b. They grow better at higher temperatures, but can survive at 5°C.

c. They grow as well at 5°C as at higher temperatures.

d. They can survive at 5°C without inputs such as water and sunlight.

b. They grow better at higher temperatures, but can survive at 5°C.

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Which of the following describes a benefit of biodiversity to an ecosystem?

a. decreases the energy flow through the ecosystem

b. increases the maximum number of trophic levels

c. increases the maximum biomass of the ecosystem

d. allows the ecosystem to withstand environmental changes

d. Allows the ecosystem to withstand environmental changes

Food production, purifying water, storing carbon, and regulating pests are all examples of what?

a. ecosystem services

b. ecosystem resilience

c. abiotic factors in ecosystems

d. biodiversity

a. Ecosystem services

In this model, the dark and light wheel-like shapes each represent different members of an animal species in an environment. The members have different tolerances to an unusually warm climate and an unusually cooler climate.

Average year, warm year, cold year

Which conclusion about biodiversity is most strongly supported by this model?

a. Biodiversity involves variations within a species, but not among several species.

b. Biodiversity has no or little effect on the survival of a species to many environmental changes.

c. Biodiversity may help species to survive either warmer or cooler temperatures, but not both.

d. Biodiversity may help a species survive a variety of environmental changes.

d. Biodiversity may help a species survive a variety of environmental changes.

Identify the choice that best completes the statement or answers the question.

How many different gametes can be produced by a tall, yellow-seeded, purple-flowered, and wrinkled-seeded pea plant (TtYyPprr)?

a. 2

b. 4

c. 6

d. 8

d. 8

Coat color in rabbits is inherited by multiple alleles for a single gene. The table describes the alleles and their inheritance.

Coat Color in Rabbits

Alleles - Phenotype (coat color) - Inheritance

C - Dark gray - Dominant to all other alleles

c ch - Chinchilla pattern of coat color - Dominant to Himalayan and white

c h - Himalayan coat color - Dominant to white

c - White (albino) - Recessive to all other alleles

Would it be possible to obtain a rabbit with Chinchilla coat color if one parent is white and the other parent has a Himalayan coat color?

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a. Yes, because the c allele is recessive to the cch allele.

b. Yes, if the Himalayan parent rabbit’s genotype is chc h .

c. No, because the parents have no alleles for Chinchilla.

d. No, because the ch allele is dominant to the cch allele.

c. No, because the parents have no alleles for Chinchilla.

Mitochondria are often described as the powerhouses of the cell. Genetic disorders can result when mitochondrial mutations occur. For example, a condition called Kearns-Sayre syndrome is caused by deletions in the mitochondrial DNA. This genetic disorder causes weakness of the muscles and other symptoms because the mitochondria are not able to provide sufficient energy to the cells. The diagram shows the possible phenotypes of children from parents who have the disease. How is Kearns-Sayre syndrome inherited? Select the best explanation.

a. Genetic disorders caused by mitochondrial mutations are examples of cytoplasmic inheritance. Only mothers transmit mitochondrial genetic disorders to their children. The male gametes have little cytoplasm. They do not contribute mitochondria to the embryos.

b. Genetic disorders caused by mitochondrial mutations are examples of polygenic inheritance, because they are transmitted from fathers to children. Mitochondria are provided by both parents in the cytoplasm of the gametes.

c. Mitochondrial genetic disorders are inherited as a dominant trait in the egg cell DNA, causing disease in the child.

d. Mitochondrial genetic disorders are inherited as a dominant trait in the sperm cell DNA, causing disease in the child.

a. Genetic disorders caused by mitochondrial mutations are examples of cytoplasmic inheritance. Only mothers transmit mitochondrial genetic disorders to their children. The male gametes have little cytoplasm. They do not contribute mitochondria to the embryos.

In a population of goats, both beige-coated and brown-coated goats are better able to blend with the rocky environment than white-coated goats. In this case, the beige and brown coat colors are favored by natural selection over the white color. Which type of pattern of natural selection would occur in this scenario?

a. Stabilizing selection

b. disruptive selection

c. normal selection

d. directional selection

b. Disruptive selection

Two species of fruit flies whose ranges overlap have different periods of mating activity. Drosophila persimilis breeds early in the morning, while Drosophila pseudoobsura breeds in the afternoon. Identify the mechanism of isolation between these two species.

a. Behavioral isolation: Each species has a courtship pattern that allows males and females to recognize each other.

b. Temporal isolation: The species remain separate because the period of most active mating differs.

c. Geographical isolation: The species remain separate because they have different breeding sites.

d. Reproductive isolation: The sperm of one species cannot fertilize the eggs of the other species.

b. Temporal isolation: The species remain separate because the period of most active mating differs.

A scientist concludes that a population of bison has reached the carrying capacity of the prairie where it lives. The birthrate and death rate of the bison population are equal to each other. What can be concluded about the rates of immigration and emigration?

a. The rates of immigration and emigration are equal to each other.

b. The rate of either immigration or emigration is zero.

c. The rate of immigration equals the birthrate.

d. The rate of emigration equals the death rate.

a. The rates of immigration and emigration are equal to each other.

The graph shows the changing populations of wolves and moose in Isle Royale National Park. Wolves are predators, and moose are their prey. Which of the following pairs of populations is most likely to increase and decrease in a similar pattern to the wolves and moose?

a. Moose and balsam fir, which are the favorite food plants of moose

b. Very old wolves and young wolf pups

c. Moose and the beneficial bacteria that live in the digestive tracts of moose

d. Male wolves and female wolves

a. Moose and balsam fir, which are the favorite food plants of moose

Bamboo is a type of grass. In the wild, pandas eat bamboo almost exclusively. For this reason, the availability of bamboo is a significant limiting factor on the panda population. Which statement describes how pandas could become extinct in the wild?

a. The bamboo population decreases so low that other limiting factors begin to affect the panda population.

b. The bamboo population decreases so low that the carrying capacity for pandas becomes zero.

c. The populations of bamboo and pandas follow a cyclical pattern of increasing and decreasing, until one of them becomes extinct.

d. The populations of bamboo and pandas both follow a pattern of exponential growth, and then both become extinct.

b. The bamboo population decreases so low that the carrying capacity for pandas becomes zero.

The human population has changed in ways that are similar to other populations. How has the human population changed since it first appeared on Earth?

a. The population has generally increased at a relatively constant rate.

b. The population has generally increased, and at rates that have varied over time.

c. The population increased rapidly until it reached its carrying capacity, where it has remained for thousands of years.

d. The population increased rapidly until it reached its carrying capacity, and then decreased at a constant rate.

b. The population has generally increased, and at rates that have varied over time.

A plant’s stem lengths were graphed from the F1 generation. Seven categories of stem length phenotypes were observed.

Stem length, highest in the middle

What pattern of inheritance is suggested by the graph?

a. codominance

b. multiple alleles

c. polygenic inheritance

d. incomplete dominance

c. polygenic inheritance

These homologous chromosomes carry different alleles of the wild type and mutant type in the fruit fly Drosophila. A cell with the homologous chromosomes undergoes meiosis, and gametes are produced. Is it possible for a chromosome of a gamete to contain the alleles for gray body and brown eyes?

a. Yes, because chromosomes are not generally inherited as units.

b. Yes, because homologous chromosomes may exchange segments by crossing over during meiosis.

c. No, because chromosomes are always inherited as complete units.

d. No, because crossing over occurs only during mitosis, not meiosis.

b. Yes, because homologous chromosomes may exchange segments by crossing over during meiosis.

Which two genes are most likely to be affected by a crossing-over event?

a. a pair of genes located adjacent to each other on a chromosome

b. a pair of genes separated by a third gene on a chromosome

c. a pair of genes located at opposite ends of a chromosome

d. a pair of genes located on different chromosomes

c. a pair of genes located at opposite ends of a chromosome

Western and Eastern meadowlarks look very similar and it is difficult to tell them apart, until they sing. Their mating songs are quite different. The Western meadowlark has a melodious song, whereas the song of the Eastern meadowlark sounds more like a whistle. Even though their ranges overlap in the central United States, they do not interbreed and are two different species. How would speciation most likely have occurred in these two species of meadowlarks?

a. Reproductive isolation occurred through behavioral isolation.

b. Reproductive isolation occurred through temporal isolation.

c. Populations were separated through geographical isolation.

d. Populations were separated through competition.

a. Reproductive isolation occurred through behavioral isolation.

Corn plants cannot be separated into discrete types or classes by their height.

(Frequency of Phenotype)

What does the graph show?

a. The graph shows the distribution of polygenic phenotypes that are expected for a trait in which two or more genes contribute to the trait.

b. The graph shows the distribution of corn plants from a monohybrid cross.

c. The graph shows the distribution of corn plants from a dihybrid cross.

d. The graph shows the distribution of single-gene phenotypes that are expected for a trait in which two or more dominant alleles control the trait.

a. The graph shows the distribution of polygenic phenotypes that are expected for a trait in which two or more genes contribute to the trait.

Study the graph to see how grasshoppers of three different body colors survive predation by blue jays in a mostly green environment. Grasshopper numbers are shown before and after blue jays preyed on them.

Which statements are supported by the data in the table?

a. If brown grasshoppers are more visible to blue jay predators in green environments, they might be less likely to reproduce, and the allele for brown color will be become less common.

b. If green grasshoppers are less visible to blue jay predators in green environments, they will be more likely to reproduce, and the allele frequency for green color will increase.

c. If natural selection produces changes in the allele frequencies of yellow-green grasshoppers in the green environment, there will be fewer of them.

d. If grasshoppers avoid an environment that matches their body color, they will be more likely to survive and reproduce successfully.

c. If natural selection produces changes in the allele frequencies of yellow-green grasshoppers in the green environment, there will be fewer of them.

In a forest ecosystem, a variety of predators compete with one another for the same prey. The predators include wolves, coyotes, foxes, and hawks. Their prey include deer, rabbits, mice, and the chickens that live outdoors on nearby farms and backyards.

Suppose that human activities, such as hunting, drastically reduce the populations of the wolves, coyotes, and foxes. Which statement best explains a likely change to the hawk population?

a. The hawk population decreases because of the natural cycle that affects predators and prey.

b. The hawk population remains constant because competition has no effect on carrying capacity.

c. The hawk population increases in a pattern of exponential growth, because the limiting factors on the population were removed.

d. The hawk population increases to a new carrying capacity that is determined by one or more limiting factors, such as the availability of food.

d. The hawk population increases to a new carrying capacity that is determined by one or more limiting factors, such as the availability of food.

Population data show that the growth rate of the world human population has been decreasing. Which statement is most useful for explaining this trend?

a. Many large, populous countries have yet to pass through the demographic transition.

b. Many large, populous countries have been passing through the demographic transition.

c. A few large, populous countries now have decreasing human populations.

d. Worldwide, the birthrate of the human population now equals the death rate.

b. Many large, populous countries have been passing through the demographic transition.

The molecular clock hypothesis states that DNA and protein sequence differences between any two species is proportional to the time since these species last shared a common ancestor.

How do molecular clocks mark time?

a. Molecular clocks mark time by mutations that tend to accumulate at the same rate in different species.

b. Molecular clocks mark time by DNA or protein sequence changes at a rate of 1% per 1 million years.

c. Molecular clocks mark time at a mutation rate of 2% per 5 million years.

d. Molecular clocks mark time by major mutations that are under natural selection pressure at different rates in different species.

a. Molecular clocks mark time by mutations that tend to accumulate at the same rate in different species.

Which of the following traits is most likely controlled by Hox genes during the development of a vertebrate embryo?

a. the formation of ribs

b. the gender of the embryo

c. the length of the neck

d. the number of limbs

d. The number of limbs

In squirrels, black fur (B) is dominant over gray fur (b). A team of scientists is studying a population of squirrels in a forest. They calculate the allele frequency and phenotype frequency for the trait of fur color over several generations. What information can they infer about the squirrel population by applying the Hardy-Weinberg equation?

a. the size of the population

b. when each allele evolved in the population

c. the rate that mutations are occurring in the population

d. whether fur color is affecting the evolution of the population.

d. Whether fur color is affecting the evolution of the population.

According to the Hardy-Weinberg principle, the frequencies of alleles remain constant in a population, but only under certain conditions. Which of these events or conditions is most likely to maintain Hardy-Weinberg equilibrium?

a. A natural disaster reduces the population to about 20 percent of its previous size.

b. Immigration from a neighboring ecosystem increases the population by 50 percent.

c. The alleles have no effect on which males and females mate and produce offspring.

d. The arrival of a new predator makes one of the alleles more advantageous than the other allele.

c. The alleles have no effect on which males and females mate and produce offspring.

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A scientist is comparing the sequences of related genes among three species. Two of the species have very similar sequences, while the sequence of the third species differs greatly from the others. The scientist uses this comparison to propose an evolutionary history of the species. Which statement best explains the usefulness of the evidence that the scientist gathered?

a. Mutations can act as a molecular clock that show when species had a common ancestor.

b. Changes in gene sequences generally occur when two species interbreed.

c. Changes in gene sequences generally occur when one species evolves into another species.

d. Although some mutations have little effect, many mutations act to distinguish one species from another.

c. Changes in gene sequences generally occur when one species evolves into another species.

The diagram describes a proposed evolutionary relationship among three ancient species, all of which were relatives of modern whales. Identify the choice that best completes the statement or answers the question.

What evidence would MOST STRONGLY support the evolutionary relationship described in the diagram?

a. data from experiments on whale behavior

b. the number of fossil discoveries of each species

c. a comparison of the fossil skeletons of the species

d. a comparison of the ages of the fossils of each species

c. A comparison of the fossil skeletons of the species

The diagram supports which of these conclusions about the three ancient species?

a. Similar body parts among the three species, such as the mouth, legs, and tail, are examples of homologous structures.

b. Similar body parts among the three species, such as the mouth, legs, and tail, are examples of analogous structures.

c. The hip and shoulder bones in each of the three species are examples of vestigial structures.

d. The hip and shoulder bones in each of the three species are examples of analogous structures.

a. Similar body parts among the three species, such as the mouth, legs, and tail, are examples of homologous structures.

On his visit to the Galapagos Islands, Darwin observed a variety of similar birds that lived either on the ground or in trees. Later, experts classified these birds as finches. Darwin had identified 14 distinct finch species, each different from one another and different from finch species that lived on the mainland. The diagram shows four of the Galapagos finches, each of which has a different type of beak. The insets compare the beaks to a type of tool.

According to Darwin's theory of evolution, each beak shape is the result of the process of natural selection. Which statement is MOST USEFUL for explaining why different beak shapes evolved in each of the four finch species?

a. Each finch species evolved from a different ancestor, each with a unique beak shape.

b. Ancestors of the finch species mated with other bird species that had variable beak shape.

c. The common ancestor of the finch species displayed the same four beak shapes of its descendants.

d. The food supply selected for beak shape as the finch species descended from a common ancestor.

d. The food supply selected for beak shape as the finch species descended from a common ancestor.

DeMarco is constructing an argument that the wings of the bird and insect are analogous structures. Which statement provides the STRONGEST evidence for this argument?

a. The two types of wings grow and develop from similar or identical embryonic tissues.

b. The two types of wings grow and develop from different embryonic tissues.

c. The two types of wings have different shapes and sizes.

d. The two types of wings are covered in different materials.

b. The two types of wings grow and develop from different embryonic tissues.

Darwin developed and proposed the Theory of Evolution during the 1800s. Since that time, due in part to advances in technology, scientists have expanded their knowledge and ideas about biological systems. Which statement describes an example of evidence acquired in the past 100 years and its relationship to the Theory of Evolution?

a. New evidence from molecular biology provides overwhelming support that all life evolved from a single ancestor.

b. New evidence from molecular biology provides evidence that life evolved from many ancestors, not a single ancestor.

c. New evidence from fossils provides evidence that one species does not descend from another.

d. New evidence from biogeography provides evidence that one species does not descend from another.

a. New evidence from molecular biology provides overwhelming support that all life evolved from a single ancestor.

The graphs show the age structure for each of three countries. The horizontal bars show the percentages of the population in each age group, by gender. Note that for Country 1, about 20 percent of the population is between the ages of 0 and 4. This is the greatest percentage of any 4-year age span in all three countries.

Which conclusion about Country 1 does its age structure support?

a. Young children have a lower death rate in Country 1 than in the other countries.

b. Young children have a higher death rate in Country 1 than in the other countries.

c. More young children live in Country 1 than in the other countries.

d. Fewer young children live in Country 1 than in the other countries.

b. Young children have a higher death rate in Country 1 than in the other countries.

Lake Tefillin is a large freshwater lake that is popular for recreation. One year, the managers of the lake introduce a population of rainbow trout to the lake. The graph shows the growth of the population over several years.

Which best describes the growth pattern of the rainbow trout?

a. Exponential growth, because the lake provides unlimited resources to the population

b. Logistic growth, because the effect of limiting factors increases with the population size

c. Exponential growth, because limiting factors are always affecting the population

d. Logistic growth, because the lake provides unlimited resources until the population reaches carrying capacity

b. Logistic growth, because the effect of limiting factors increases with the population size

Dr. Osgood and her team are using a computer simulation to study the relationships between predator and prey. The simulation assumes that both predator and prey populations are minimally affected by other animals. The results of one version of the simulation are shown in the graph.

Dr. Osgood decides to continue the simulation, but with the introduction of a second predator species. Both the original and new predators hunt the same prey in the same environment, and they do not hunt or eat other food. As predicted by the competitive exclusion principle, which of the following results is most likely?

a. The populations of the two predator species increase and decrease in the same cycle.

b. The populations of the two predator species increase and decrease in opposite cycles.

c. The population of one predator species, but not both, decreases to a small number or zero.

d. The population of the prey species, but not the two predators, decreases to a small number or zero.

c. The population of one predator species, but not both, decreases to a small number or zero.

Zoe is studying a mountainous region where a glacier is melting and retreating. She constructs the timeline shown below to show her prediction of how the region will change over time.

Why are the changes shown in the diagram classified as primary succession, and not secondary succession?

a. The process results in the appearance of a climax community.

b. Many intermediate communities appear before the climax community.

c. The climax community appears after hundreds of years.

d. The process begins with pioneer species growing on bare rock.

d. The process begins with pioneer species growing on bare rock.

Which of the following events would be MOST LIKELY to permanently disturb the climax community that Zoe predicts will arrive?

a. a fire that burns down half of the trees in the community

b. the introduction of grasses and other small plants

c. the spread of an invasive fungus that kills the oak trees

d. the arrival of deer that feed on the leaves of the trees

c. the spread of an invasive fungus that kills the oak trees

Many bacteria can invade respiratory passageways in humans and other animals. The bacteria can cause pneumonia and other diseases. Why is the concept of a microbiome useful for studying these bacteria and the diseases they cause?

a. The bacteria are affected by the external biome, such as tundra, rain forest, or desert.

b. The bacteria are affected mostly by their immediate environment, which is respiratory tissue.

c. All living bacteria interact within a biome that extends across Earth.

d. All living bacteria and their hosts interact within a biome that extends across Earth.

b. The bacteria are affected mostly by their immediate environment, which is respiratory tissue.

Homologous chromosomes pair to form a tetrad and cross over.

Meiosis or mitosis?

Meiosis

Homologous chromosomes line up at the center of the cell.

Meiosis or mitosis?

Meiosis

Homologous pairs separate and move towards opposite poles of the cell.

Meiosis or mitosis?

Meiosis

Two genetically not identical, haploid daughter cells are formed.

Meiosis or mitosis?

Meiosis

Sister chromatids separate and move to opposite poles.

Meiosis or mitosis?

Mitosis

Replicated chromosomes line up at the center of the cell.

Meiosis or mitosis?

Mitosis

Two genetically identical, diploid daughter cells are formed.

Meiosis or mitosis?

Mitosis

One dog is heterozygous for black fur (Bb), and its mate is homozygous for blonde fur (bb). What is the probability of one of their puppies having black fur? Explain.

Half, explain by drawing punnett square

The cladogram shown below represents the evolutionary relationship among five modern species, as well as five derived characters of the lineages. Although derived characters may be lost, none of the derived characters shown in the cladogram were lost in the five modern species.

How could the cladogram shown here be expanded or revised to show the tree of all life?

Expand it to include all the other groups of living things. If you keep expanding and adding groups, you will end up with the full tree of life.

On his visit to the Galapagos Islands, Darwin observed a variety of similar birds that lived either on the ground or in trees. Later, experts classified these birds as finches. Darwin had identified 14 distinct finch species, each different from one another and different from finch species that lived on the mainland. The diagram shows four of the Galapagos finches, each of which has a different type of beak. The insets compare the beaks to a type of tool.

According to Darwin, how do the processes of natural selection and descent with modification help to explain the variety among the Galapagos finches?

Natural selection and descent with modification.

Descent with modification - they all came from one common ancestor

Natural selection - they adapted to eat the food around them

Why are the stages of ecological succession likely to occur in the order that Zoe predicts in the model, and not in another order?

it shows primary succession