B.A.M.S Biology Cumulative (-Taxonomy)

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In a population of humans, the frequency of blue eyes is 0.09. If having blue eyes is the recessive phenotype, what is the frequency of the recessive allele? 0.3 0.9 0.18 0.36

0.3

The allele for curly hair is incompletely dominant. If a mother is homozygous for curly hair and the father is homozygous for straight hair, what percentage of the offspring will exhibit characteristics of both parents? 25 percent 50 percent 75 percent 100 percent

100%

When Mendel crossed purebred purple flowering plants (PP) with purebred white flowering plants (pp), what were the flower colors of the resulting offspring? 25 percent white and 75 percent purple 50 percent white and 50 percent purple 100 percent purple 100 percent white

100% purple

In a population of humans, the frequency of straight hair is 34 percent. If straight hair is the recessive phenotype, what is the frequency of the homozygous recessive genotype? 17 percent 34 percent 66 percent 68 percent

34%

Purple flowers are dominant over white flowers. A heterozygous purple flower is crossed with another heterozygous purple flower. The ratio of purple to white would be

3:1

A plant can produce either purple flowers or white flowers. What is the probability of purple-flowered offspring if two plants that are heterozygous for purple flowers are crossed? 1:4 2:4 3:4 4:4

3:4

A pea plant that has round seeds has the genotype Rr. It is crossed with a pea plant that has wrinkled seeds and the genotype rr. What is the probability that the offspring will have wrinkled seeds? 0 percent 25 percent 50 percent 75 percent

50%

Tall pea plants are dominant over short pea plants. If there are 200 short plants in the F2 generation from a cross that followed Mendel's methods, about how many plants will be tall in that generation? 200 300 600 1,000

600

Parents that are heterozygous for having freckles (dominant) are crossed. Which represents the ratio of their offspring? Twenty-five percent have freckles. Twenty-five percent are Ff. Seventy-five percent have freckles. Seventy-five percent are Ff.

75% have freckles

If you inherit the genotype AO for blood from your parents, what blood type do you have? A B AB O

A

Why is it important to know a person's rhesus factor before a blood transfusion? A patient who is Rh+ can receive only Rh- blood. A patient who is Rh- can receive only Rh+ blood. A patient who is Rh+ can receive only Rh+ blood. A patient who is Rh- can receive only Rh- blood.

A patient who is Rh- can receive only Rh- blood.

Which blood type could be given as a transfusion for patient with AB blood when the RH factor is unknown? O+ A+ AB+ AB-

AB-

The fossil record indicates that the earliest hominids most likely originated on which continent? Africa Asia North America Europe

Africa

How are sex-linked traits inherited? Alleles are passed from the parents' sex chromosomes to nonsex chromosomes in the offspring. Alleles are passed from the parents' nonsex chromosomes to the sex chromosomes in the offspring. Alleles are passed from the parents' sex chromosomes to the sex chromosomes in the offspring. Alleles are passed from the parents' nonsex chromosomes to nonsex chromosomes in the offspring.

Alleles are passed from the parents' sex chromosomes to the sex chromosomes in the offspring.

Scientific investigations often lead to the formulation of new scientific questions. The observations Charles Darwin made during his time aboard the H.M.S. Beagle prompted him to ask which question? Do living organisms change over time and, if so, how? Are the finches of the Galapagos Islands the same as those on the mainland? Can selective breeding occur in nature? Can the accumulation of gradual changes in a population lead to a new species over time?

Do living organisms change over time and, if so, how?

A population of snakes that eat small rodents enters a new habitat. In the new habitat, there are many species of rodents, and their populations are high because there are few natural predators. What will most likely be the effect on the genetic variation of the snake population? Genetic variation will increase because of a selective pressure. Genetic variation will increase because of a new habitat and food source. Genetic variation will decrease because of a selective pressure. Genetic variation will decrease because of a new habitat and food source.

Genetic variation will increase because of a new habitat and food source.

Which was Charles Darwin's contribution to the study of biology? He was the first person to recognize that organisms change over time. He believed that organisms adapted through the inheritance of acquired traits. He explained how traits are passed from parents to offspring. He proposed that natural selection is the primary mechanism of evolution.

He proposed that natural selection is the primary mechanism of evolution.

A scientist wrote a paper titled "Directional Selection in Action" after observing a population of mice for 15 years. The mice typically preferred to eat berries, although a few would also eat insects. After a drought in year 3, the scientist observed that more mice were eating insects. By year 10, most of the mice in the population ate insects in addition to berries. Which best describes her article? Her title is accurate because two opposite extremes are favored. Her title is accurate because one extreme is favored. She should change her title because she is observing stabilizing selection. She should change her title because selection cannot be observed.

Her title is accurate because one extreme is favored.

In the African savanna, more wildebeests are born than the environment can support. Which is most likely to happen over a period of years as a result? The chances for survival of the population are reduced. New food sources are discovered and become the regular diet. Individuals that are well suited to the environment reproduce, and those that have lesser adaptations die before they reproduce. The environment adapts by providing more resources to the growing population, increasing the chances of survival for individuals within the habitat.

Individuals that are well suited to the environment reproduce, and those that have lesser adaptations die before they reproduce.

Protists are a group of organisms that are characterized as eukaryotes (they have cells with nuclei) that are neither plants nor animals nor fungi. They are very diverse, and there are many hypotheses about their classification. The cladogram for protists is constantly changing and, sometimes, there are opposite hypotheses that both have data to support them. What is the implication of a changing hypothesis? It is acceptable because data are still being collected. It is acceptable because everything in science should always change. It is not acceptable because the correct answer needs to be found. It is not acceptable because science never changes.

It is acceptable because data are still being collected.

What can be known about Mendel's five-part hypothesis? It is an answer to a scientific question and is based mostly on research. It identifies three alleles for each gene. It is an answer to a scientific question and is based mostly on prior knowledge. It identifies one allele for each gene.

It is an answer to a scientific question and is based mostly on research.

If blood is in short supply, which blood type would be the most beneficial to have on hand if someone needed a blood transfusion? O+ O- AB+ AB-

O-

Why did Gregor Mendel use peas in his experiments? Peas grow very slowly. Pea reproduction cannot be controlled. Peas normally produce very few offspring. Peas have characteristics that have two forms.

Peas have characteristics that have two forms.

Mendel crossed two plants that were heterozygous for purple flower color. Which genotypes could he have used to represent the cross? PP ´ PP Pp ´ Pp pp ´ pp Pp ´ PP

Pp ´ Pp

A student argues that being separated geographically is the only way for speciation to occur. Why is he wrong? Speciation does not usually rely on geographic isolation. Speciation can occur from biological forces as well. Speciation can occur from variation as well. Speciation does not result from adaptive radiation.

Speciation can occur from biological forces as well.

Gregor Mendel crossed homozygous tall plants (TT) with homozygous short plants (tt). All the resulting offspring were tall. From these results, what conclusion did Mendel draw? Tallness is a dominant trait. The word homozygous always means dominant. Only dominant alleles are passed on to offspring. The alleles of the offspring were recessive.

Tallness is a dominant trait.

Marsupials are found in North America and Australia, but they would not have been able to swim across the ocean. According to scientists, how did this group of organisms come to live on two separate continents? Marsupials used to have adaptations that allowed them to swim but lost these adaptations over time. The two groups of marsupials evolved independently of one another on two separate continents. The continents were once connected, and marsupials were able to migrate over the land. The oceans were shallow in prehistoric times, which allowed the marsupials to travel from one continent to another.

The continents were once connected, and marsupials were able to migrate over the land.

Darwin hypothesized that new species could appear gradually through small changes in an ancestral species. Which observation that he made about finches most supports that hypothesis? The finches all ate the same materials as the mainland population. The finches were all relatively small compared to the mainland population. The finches all appeared to be related but differed from the mainland population. The finches were identical to the mainland population.

The finches all appeared to be related but differed from the mainland population.

Which best describes the lower body structures of humans and chimpanzees? The big toes of humans and chimpanzees are enlarged. The human foot has two arches, but the chimpanzee foot only has one. Human knees are very mobile, but chimpanzee knees are stabilized by tendons. The blades of the human pelvis are not rotated inward like those of the chimpanzee.

The human foot has two arches, but the chimpanzee foot only has one.

Scientists base many of their investigations on questions that test accepted theories. Which outcome of an investigation would cause a scientist to ask a different question? The observed results are different from the expected results. The investigation had many sources of error. Another scientist proposed the same theory. The expected results could be explained in different ways.

The observed results are different from the expected results.

What is the best description of an organism that is fit for natural selection? The organism is physically stronger than competing organisms. The organism is physically stronger than organisms of a different species. The organism is better able to survive and pass on traits to offspring than competing organisms. The organism is a member of a population in which every member survives without competing.

The organism is better able to survive and pass on traits to offspring than competing organisms.

Which statement best describes the potential confusion in early studies of inheritance patterns for skin color? The polygenic trait appeared as incomplete dominance. The polygenic trait appeared as codominance. Incomplete dominance appeared to be a polygenic trait. Codominance appeared to be a polygenic trait.

The polygenic trait appeared as incomplete dominance.

Some people have freckles, and some people do not have freckles. If a child has freckles, at least one parent has freckles. However, the child may have a sibling that does not have freckles. Which statement best describes the presence of freckles? Freckles are not determined by DNA. There are two alleles for freckles. There is no dominant allele for freckles. Freckles are determined by two genes instead of by one.

There are two alleles for freckles.

Which best describes derived characteristics? They are newly evolved traits. They appear in all the ancestors. They appear at the end of each branch. They stem from primary characteristics.

They are newly evolved traits.

Scientists often use fruit flies as a method to test hypotheses about human genes. Why are fruit flies advantageous in the study of human inheritance? They can self-pollinate. They lack nucleic acids. They are very different from humans. They reproduce quickly and take up little space.

They reproduce quickly and take up little space.

Why did Mendel study pea plants? They reproduce asexually and have one trait that is easy to observe. They reproduce asexually and have many traits that are easy to observe. They reproduce sexually and have one trait that is easy to observe. They reproduce sexually and have many traits that are easy to observe.

They reproduce sexually and have many traits that are easy to observe.

Why did Gregor Mendel study pea plants? They exhibit only a single trait. They produce flowers. They are easy to grow. They reproduce sexually.

They reproduce sexually.

If two organisms are in the same clade, what can you predict about their relationship? They are not closely related. They share a common ancestor. They compete for resources. One organism evolved into the other organism.

They share a common ancestor.

What is the value of a transitional fossil? Transitional forms show the evolutionary steps between species. Transitional forms are analogous fossils. Transitional forms discredit the theory of evolution. Transitional forms are proof of punctuated equilibrium in evolution.

Transitional forms show the evolutionary steps between species.

Which statement would least likely be used to describe variation? Variations are inherited differences between individuals of the same species. Variations that decrease reproductive success are more likely to be passed on. Variations may result in changes to an entire population after many generations. Variations provide some individuals with an advantage.

Variations that decrease reproductive success are more likely to be passed on.

A scientist makes the argument that she has found DNA evidence that shows that evolution does not exist. What would her evidence have to show for her to be correct? Strong genetic similarities in closely related organisms and weak genetic similarities in distantly related organisms. Weak genetic similarities in closely related organisms and strong genetic similarities in distantly related organisms. Strong physical similarities among closely related organisms and also among distantly related organisms. Weak physical similarities among closely related organisms and also among distantly related organisms.

Weak genetic similarities in closely related organisms and strong genetic similarities in distantly related organisms.

The concept of evolution by way of natural selection is a central tenet in biology that has been tested in numerous ways by many scientists but is not yet considered a law. Evolution by way of natural selection is most likely which type of concept? a hypothesis that can be accepted as true based on repeated experimentation with similar results a likelihood based on the chance that a particular event will or will not occur a statement of fact that is generally accepted to be true and universal because it has always been observed to be true a probability that is an answer to a scientific question and is based on prior knowledge or research

a hypothesis that can be accepted as true based on repeated experimentation with similar results

Which represents polygenic inheritance of traits? a cow that has red and white dominant coloring a mix of blue, green, and brown eye colors a plant that has pink flowers produced from a plant that has red flowers and a plant that has white flowers a plant that has green seeds produced from a plant that has yellow seeds and a plant that has green seeds

a mix of blue, green, and brown eye colors

A population of squirrels lived together in a forest. An event occurred that caused the population to diverge into two different species over a long period of time. Which of the following is most likely the event that occurred? There was an increase in the predators in the forest. A natural disaster occurred that separated squirrels. The winters were unusually cold in the forest. A disease affected the squirrel population in the forest.

a natural disaster occured that separated squirrels

Which statement best describes human eye color? an incompletely dominant trait that follows non-Mendelian inheritance patterns a polygenic trait that follows non-Mendelian inheritance patterns an incompletely dominant trait that follows Mendelian inheritance patterns a polygenic trait that follows Mendelian inheritance patterns

a polygenic trait that follows non-Mendelian inheritance patterns

A scientist has been tracking and studying a population of deer in Yellowstone National Park. He surveys the population every six months. Usually, the population is thriving and has a gene pool with a wide variety of traits. But during one six-month period, an event occurred that affected the population, and when the scientist returned, the amount of genetic variation had decreased significantly. Which of the following is most likely the event that occurred to change the population? Yellowstone National Park expanded its borders. A population of wolves was introduced into Yellowstone National Park. The amount of disease in the deer population decreased. More grass and shrubs were planted in Yellowstone National Park.

a population of wolves was introduced into Yellowstone National Park

What is natural selection? a process that selects variations that help with survival and that spreads the variations to more offspring a process through which nature selects an individual within a population for extinction the difference in heritable traits within a population the process of nature that causes random variations to appear in the offspring of every generation

a process that selects variations that help with survival and that spreads the variations to more offspring

What is a gene? a section of a protein that codes for DNA the alternate version of a trait the visible trait in the F1 generation a section of DNA that codes for a specific trait

a section of DNA that codes for a specific trait

What is a gene? the different forms of a trait a segment of DNA that is the basic unit of heredity the appearance or characteristics that are seen in an organism an organism's allele combination

a segment of DNA that is the basic unit of heredity

Stick insects, also called walking sticks, are typically found in tropical and subtropical forests and grasslands. The insects are able to camouflage themselves by living among twigs in their environment. What is this an example of? adaptation biodiversity isolation variation

adaptation

What is the main difference between adaptive radiation and other forms of speciation? Adaptive radiation is a mechanism for evolution. Adaptive radiation happens over a relatively short time. Adaptive radiation requires a founding population. Adaptive radiation occurs only on islands.

adaptive radiation happens over a relatively short time

Which was NOT a result of the 1898 discovery of the four blood types? improved blood transfusion safety effective blood preservation solutions developed elements of blood separated via centrifuge all blood types made compatible with each other

all blood types made compatible with each other

Nucleic acids offer variability because they contain alternate forms of genes called ________

alleles

Which are different forms of the same gene? genotypes phenotypes alleles traits

alleles

Which combination of alleles best describes a sex-linked trait? heterozygous alleles homozygous alleles alleles that are carried on X and Y chromosomes alleles that are carried on somatic cells

alleles that are carried on X and Y chromosomes

Which environmental factor could lead to a decrease in genetic variation in a population of tuna? an increase in food availability an increase in pollution a decrease in tuna fishing a decrease in tuna predators

an increase in pollution

Which structures are similar in function, but do not guarantee that the organisms are related? analogous structures homologous structures vestigial structures transitional structures

analogous

Which of the following best defines gene flow? the sum of all genetic traits in a population's individuals at a given time any movement of genes from one population to another any movement of organisms from one environment to another the random change in the frequency of an allele in a population

any movement of genes from one population to another

A skull from the genus Homo that dates from approximately 750,000 years ago is discovered. Where would the foramen magnum most likely be located? at the back of the skull at the front of the skull at the bottom of the skull at the top of the skull

at the bottom of the skull

Which describes the modern classification system? based on evolutionary relationships called Linnean classification based on similar appearances called Darwinian classification

based on evolutionary relationships

Two species of flies, Drosophila melanogaster and Drosophila simulans, can mate. They usually do not mate, however, even if they are kept together in a laboratory. Males court the females of both species, but the females prefer to mate with males of their own species. Which isolating mechanism does this describe? behavioral temporal artificial anatomical

behavioral

Gentoo penguins will present a mate with a pebble that they find to attract a mate. Emperor penguins have a specific call and movement that they make to attract a mate. Which type of isolation do these penguins demonstrate? temporal isolation behavioral isolation geographical isolation anatomical isolation

behavioral isolation

Darwin hypothesized that new species could appear gradually through small changes in an ancestral species. What experiment did he conduct to test this hypothesis? the breeding of finches the breeding of pigeons the observation of plants the observation of dog breeds

breeding of pigeons

Which of these statements best sums up evolution? rapid change in species' habits and features punctuated change in a population change in a population through new species being made change in a population through genetic variation over time

change in a population through genetic variation over time

Phylogenetic trees are also called cladograms

cladograms (must include the s or it won't count on edg.)

The fossil record shows that two groups of organisms are related, which means they share a _________.

common ancestor

A scientist wants to examine a genetic disease in humans. The scientist hypothesizes that the disease can be treated by using gene therapy. Humans take a long time to reproduce and develop, so the scientist will have to give up on testing the hypothesis. test the hypothesis for a very long time. develop new methods to test the hypothesis. find a way to make humans reproduce faster.

develop new methods to test the hypothesis.

A population that is becoming less diverse because of its individuals tending to be larger is most likely experiencing ______selection.

directional

A population of pigs lives on an island together with burrowing termites. Pigs that have the longest snouts tend to survive better. Over time, most of the pig population is made up of individuals that have very long snouts. This is an example of which type of selection? directional selection disruptive selection stabilizing selection ecosystem selection

directional selection

An example of a polygenic trait is

eye color, which is controlled by many interacting genes

Which lists the correct sequence of events for evolution to occur through isolation? founding population arrives, biogeographic isolation occurs, genetic changes occur, reproductive isolation results genetic changes occur, founding population arrives, reproductive isolation results, biogeographic isolation occurs biogeographic isolation occurs, founding population arrives, genetic changes occur, reproductive isolation results founding population arrives, genetic changes occur, biogeographic isolation occurs, reproductive isolation results

founding population arrives, biogeographic isolation occurs, genetic changes occur, reproductive isolation results

Changes in the gene pool can occur due to various mechanisms. From 1892 to 1954, millions of individuals emigrated (moved out) from countries across the Atlantic Ocean to the United States. Many of these individuals entered through Ellis Island, a federal immigration station in New York. Which mechanism affected the gene pool of the immigrants that entered the United States through Ellis Island? genetic drift gene flow gene mutation natural selection

gene flow

In a population of seals, most of the seals have similar coloring. However, one seal has albinism. This seal is white and is almost completely blind. What is most likely the cause of this difference from the rest of the population? gene flow natural selection gene mutation genetic drift

gene mutation

Which factor do biologists calculate when they determine whether a population is in Hardy-Weinberg equilibrium? mutation rate genotype frequencies number of phenotypes rate of migration

genotype frequencies

Imagine a population of rabbits with fur color that ranges from black to white. If this population were put in an area that has dark rocks that camouflage the black rabbits, as well as light stones that hide the white rabbits, what would most likely happen to the gray rabbits? Gray rabbits would blend into either environment. Gray rabbits would adapt to have black fur. Gray rabbits would be eliminated by predators. Gray rabbits would mutate to white fur.

grey rabbits would be eliminated by predators

Mendel's pea plants had either purple or white flowers. This means that the plants can self-pollinate. have two recessive traits. have two alleles for the gene. have two copies of a gene from one parent.

have 2 alleles from the same gene

What was Thomas Hunt Morgan's main contribution to science? He discovered that certain traits were linked to the X chromosome. He discovered that certain traits were linked to the Y chromosome. He created the first white-eyed female Drosophila. He created the first white-eyed male Drosophila.

he discovered that certain traits were linked to the X chromosome

What does the notation Rr mean to geneticists? heterozygous alleles homozygous alleles dominant alleles recessive alleles

heterozygous alleles

Which term describes an organism that has identical alleles for a trait? homozygous heterozygous dominant recessive

homozygous

Which statement is a reason that modern human populations never reach Hardy-Weinberg equilibrium? Evolution rarely occurs in human populations. Mating is random in human populations. Humans live in small, isolated groups. Humans regularly travel all over the globe.

humans regularly travel all over the globe

Some flowering plants appear to have offspring that have traits that are intermediate between those of the parents. Which type of dominance is exhibited by the offspring? complete dominance blended dominance codominance incomplete dominance

incomplete dominance

An increase in food and a decrease in predators would most likely ______ genetic variation in a population.

increase

Which lists the correct order of evolutionary history? crabs, jellyfish, reptiles mammals, amphibians, crabs vertebrate fish, crabs, mammals jellyfish, reptiles, mammals

jellyfish, reptiles, mammals

Which of Mendel's laws or principles states that gametes carry one allele for each trait? principle of dominance law of independent assortment law of segregation law of genetics

law of segregation

Which genotype does pq represent in the Hardy-Weinberg equation? one that has a dominant allele and a recessive allele one that has two dominant alleles one that has two recessive alleles one that has a dominant allele and a neutral allele

one that has a dominant allele and a recessive allele

Which organisms are most likely to survive in a population in which disruptive selection is occurring? organisms that have average traits organisms that have extreme traits organisms that are sexually selected organisms that are the largest and strongest

organisms that have extreme traits

A new fossil is found, and scientists are debating whether it can be considered a part of the human genus Homo. What piece of evidence would best indicate that the fossil is human? large jaw bone for muscle attachment pelvic blades rotated inward very long arms thick rib cage

pelvic blades rotated inward

Which adaptation makes bipedalism possible? opposable digits large brain foramen magnum in back of skull pelvis rotated inward

pelvis rotated inwards

Veronica wrote Charles Darwin's main points on the board, but she made a mistake in one point. 1. Since more offspring are produced than an environment can support, organisms within a population must compete for resources to survive. 2. Due to variations within the population, some competitors will be better equipped for survival than others. 3. The best-equipped organisms will survive and will produce well-equipped offspring. 4. Variations that help with survival will be passed on to future generations and will rapidly change the whole population. Which point is flawed as written above? point 1 point 2 point 3 point 4

point 4

Which is most likely to occur in a population in Hardy-Weinberg equilibrium? evolution mutation gene flow random mating

random mating

Horses and donkeys can mate, but they produce a mule, which is always a sterile animal. This means that they cannot produce viable offspring and are ______ isolated.

reproductively

Dr. Digger, a paleontologist, finds a fossil that he describes in his journal. The creature was approximately 1 meter long, with its backbone fused into a large shell covering the body cavity. It had a beaklike mouth, without teeth, and all four limbs were in the form of flippers. Based on anatomical similarities, to which modern animal is Dr. Digger's creature most closely related? zebra bony fish sea turtle snake

sea turtle

A population of chimpanzees was separated when the forest that they lived in had a section cut down and a town was built. After a long period of time, the chimpanzees came back into contact but were incapable of breeding. Which of the following best describes the process that occurred? adaptation speciation convergent selection stabilizing selection

speciation

A population contains short plants and tall plants. The short plants are not able to compete with tall plants for sunlight. The tall plants, however, are more susceptible to wind damage. Which type of selection are the plants experiencing? directional selection disruptive selection species selection stabilizing selection

stabilizing selection

A scientist discovers a new organism that is related to clownfish. What can the scientist discover by using molecular clocks? the date that the organism first appeared in the fossil record the age of the organism the amount of time that the two species have been evolving apart the number of years that fish have existed

the amount of time that the two species have been evolving apart

Which of the following could result in speciation from biogeographic isolation? the isolation of two populations of the same species the isolation of two individuals of the same species the isolation of two populations of different species the isolation of two individuals of different species

the isolation of two populations of the same species

Why do species evolve during adaptive radiation? to fill different niches to create variation to become reproductively isolated to provide evidence of evolution

to fill different niches

What is the purpose of using a pedigree? to study the causes of traits that are acquired during an organism's life to understand patterns of inheritance in organisms to determine mating patterns in organisms to identify traits that are acquired during an organism's life

to understand patterns of inheritance in organisms

Wisdom teeth are the third and final set of human molars that come in during the late teens or early twenties. In some cases, these teeth come in without problems, but they often have to be removed due to misalignment in the jaw, as shown below. Removal of the teeth does not cause any long-term complications in regard to eating. Which type of anatomic structure are wisdom teeth? vestigial homologous analogous heterologous

vestigial

Dogs have a reduced nonfunctional digit on their paws known as a dewclaw. What is this an example of? analogous structure homologous structure vestigial structure mutated structure

vestigial structure


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