Bio CH 12

5 Which characteristic would contribute most directly to fitness? Growing to a large size Living a long time Having the most offspring Being able to catch the most prey

Having the most offspring

10 Which step in the theory of natural selection is used by humans for artificial selection? Populations produce more offspring than the environment can support. Some variation can be passed on to offspring. Differential survival and reproduction exists among individuals in a population. Individuals in a population vary.

Differential survival and reproduction exists among individuals in a population. Individuals in a population vary.

49 How does antibiotic use cause evolution in a population of tuberculosis bacteria? People who take antibiotics too often become susceptible to a wider variety of bacterial infections. Antibiotics kill bacteria without resistance, leaving only resistant bacteria. Antibiotics cause other types of resistant bacteria to change into tuberculosis bacteria. Antibiotics cause mutations in the DNA of bacteria.

Antibiotics kill bacteria without resistance, leaving only resistant bacteria.

44 Why have public health officials once again become very concerned about tuberculosis in the 21st century? M. tuberculosis is difficult to grow in the lab. Antibiotic-resistant strains of tuberculosis are on the rise. The immune systems of infected people cannot recognize and kill M. tuberculosis. Tuberculosis can lie dormant for months.

Antibiotic-resistant strains of tuberculosis are on the rise.

35 How is artificial selection different from natural selection? Artificial selection occurs rapidly in one generation. Artificial selection only occurs in modern times. Artificial selection is directed by human choice. Artificial selection changes traits but not genes.

Artificial selection is directed by human choice.

37 What happens when patients with tuberculosis do not follow their combination drug schedule carefully? Bacteria particles are destroyed in all cells but the lung cells. Bacteria develop resistance to every one of the drugs. Lung tubercles remain walled off. Bacteria populations decline and do not rise to their original high levels.

Bacteria develop resistance to every one of the drugs.

64 How does the use of multiple drugs to combat an infection influence evolution? It makes the evolution of resistance in bacteria less likely. It makes the evolution of resistance in bacteria more likely. It makes extinction of bacteria more likely. It makes the evolution of humans with poor immune systems more likely.

It makes the evolution of resistance in bacteria less likely.

61 Drug resistance to anti-HIV drugs is a serious problem. Why does drug resistance appear so rapidly in HIV? It's sexually transmitted. It has a high rate of mutation. It's sensitive to antibiotics. It's found in the blood.

It has a high rate of mutation.

50 Which of the following explains how people are affected by Mycobacterium tuberculosis infections? The human digestive system is invaded by the bacteria and colon cancer may result. Patients' immune systems stop functioning and they get many infections. The bacteria destroy lung tissue and most patients die rapidly. Most infections are symptomless, but active lung disease occurs in 10% of infected people.

Most infections are symptomless, but active lung disease occurs in 10% of infected people.

23 How would evolutionary biologists define the fitness of an organism? The ability of a population to adapt The ability of an individual to stay healthy The ability of an individual to survive and reproduce The ability of a population to survive

The ability of an individual to survive and reproduce

1 What factor is most important in determining the way that a population evolves? The average life span for each member of the population The average number of offspring produced by each member of the population The environment The size of the population

The environment

20 In the process of natural selection, what is selection? A force that causes an organism to develop an adaptation The number of offspring produced by competing members of a population The degree of fitness of an organism relative to the environment The environmental change that eliminates the less fit individuals

The environmental change that eliminates the less fit individuals

29 Which event is the most direct result of natural selection on a population? New alleles are created when confronted with a new environment. Members of the population start reproducing more rapidly. The frequency of some alleles changes in the population. Proteins lose some functions.

The frequency of some alleles changes in the population.

17 Why might an extremely drug-resistant bacterial strain found in a hospital patient not infect other patients? The strain went dormant and was waiting for the right conditions to reappear. The strain reverted back to bacteria sensitive to common medicines. The strain must have transformed into a new bacterial species. The strain may have been less fit in other ways and died off before infecting others.

The strain may have been less fit in other ways and died off before infecting others.

26 Some bears in a nearby forest have a much darker coat color than most of the other bears. Is this darker color an adaptation? The trait is only an adaptation if it gives the bears an advantage in their habitat. Yes, all variations are adaptations in a specific population. The coat color of the dark bears' parents must first be known. No, adaptations are traits developed only to help an organism survive.

The trait is only an adaptation if it gives the bears an advantage in their habitat.

7 After a rapid change in climate, one population of bird quickly adapts to the change, but others in the area do not. What conclusion could be made about the quickly adapting population? They already had alleles for adaptations to the new conditions. They reproduced more slowly than the nonadapting population. They had a higher rate of mutation than the other population. They had a greater need to evolve than the other population.

They already had alleles for adaptations to the new conditions.

34 Why are some people resistant to HIV? They have been immunized in an experimental program. They never engage in risky behavior and thus can't become infected. They have a strong immune system that clears the virus completely. They can't be infected with HIV even when exposed.

They can't be infected with HIV even when exposed.

68 Which description applies to individuals who are well adapted for a particular environment? They may or may not be equally fit in another environment. They will mutate to become fit in other environments. They are at a disadvantage in other environments. They are the best fit for all other environments.

They may or may not be equally fit in another environment

55 A population of birch trees is preyed upon by beetles that burrow into bark. Which tree would be the most fit? a tree that has thicker bark a tree that grows to be the tallest a tree that has thick, strong roots a tree with more active photosynthetic enzymes

a tree that has thicker bark

58 What bacterial variant would be most likely to survive in the human digestive system? a variant that reproduces slowly a variant with a coating that is resistant to an acidic environment a variant that easily attaches to hard surfaces a variant that thrives at temperatures close to 100°C

a variant with a coating that is resistant to an acidic environment

31 The blueberries found in a typical grocery store have several gene differences compared with wild blueberries. What has caused this difference? artificial selection genetic engineering a change in the environment natural selection

artificial selection

40 What process can result from natural selection? Traits to be passed from parents to offspring Evolution Adaptations to occur via mutation Random fertilization

evolution

12 True or false: Any allele present in a population exists to increase fitness.

false

13 True or false: The goal of natural selection is to make extreme traits more common.

false

62 True or false: Any individual organism may evolve with enough time and a mechanism to generate variation.

false

36 True or false: Any trait that is controlled by genes can be acted on by natural selection.

true

48 Which situation could lead to evolution in a plant population? Development of houses in a nearby area An earthquake A drought A fire

A drought

27 Resistant bacteria have proteins that disable or counteract antibiotics. Antibiotic resistance is a genetic trait that can be passed on to offspring. Combination drug therapy can help prevent the evolution of antibiotic resistance. The likelihood that an individual bacterium carries the genetic variations that allows it to disable two different antibiotics is very low. The bacterium that caused tuberculosis was in decline, but now strains exist that are nearly untreatable. Antibiotic resistance would be predicted to become more common in tuberculosis bacteria after antibiotic use, which indeed occurred not long after the introduction of antibiotics in the 1940s. As individuals, we can prevent antibiotic resistance from spreading if we are thorough when using antibiotics, even if our infection contains a few drug-resistant bacteria. Antibiotics help to keep the bacterial population low for a long enough period that an individual's immune system can finish off even drug-resistant individuals. Natural selection often causes a patient's recurrent infection to be more dangerous than the initial one. Bacteria with a mutation for antibiotic resistance are more likely to survive a first, or incomplete, round of antibiotics. Once they multiply, the resulting infection will be more difficult to treat.

.....

39 1. The root -biotic means pertaining to life. 2. The root -osis indicates a condition. 3. The root adapt- means to fit in. 4. The root anti- means in opposition to. 5. The root patho- means disease. 6. The root tubercul- means small swelling. 1. A(n) pathogen is an entity that causes disease. 2. A(n) antibiotic is a drug that inhibits the growth of microorganisms. 3. Tuberculosis is a condition characterized by the development of swollen nodules in the lungs that interfere with oxygen intake. 4. A(n) adaptation is a trait in an organism that increases its chance of survival or reproduction.

.....

67 How many people carry Mycobacterium tuberculosis? 2 billion 250,000 500,000 1 million

2 billion

54 Part A Different finch species have beaks of different shapes and sizes. What do these beak differences tell us? Different finch beak shapes are evidence that individual birds changed their beaks so that they could feed efficiently. Different finch beak shapes are evidence that several finch species with different beak types came to the Galápagos Islands from the mainland. Different finch beak shapes are evidence that all Galápagos finches share a common ancestor. Different finch beak shapes are evidence that finch species adapted to different environments over many generations. Part B Genetic evidence supports which of the following explanations for the presence of 13 different finch species on the Galápagos islands? Many years ago, a small population of a single finch species migrated to the islands and evolved into the current 13 species. The 13 species have existed on the Galápagos islands since the islands first formed. Many years ago, more than 13 different species of birds migrated to the islands. The current 13 finch species are the only species that survived. Each of the 13 species migrated to the islands at different times over the years. Part C A bar chart comparing the number of birds for 9 beak depths before and after the drought in 1977. The number of birds divides into 2 groups: the first one represents the initial population before the drought and the second one represents drought survivors. For the beak depth of 7.3 millimeters, the total amount of the population is 2; the number of survivors is 0. For the beak depth of 7.8 millimeters, the population is 12, and there are 2 survivors. For 8.3 millimeters, the population is 30, and there are 4 survivors, respectively. For 8.8 millimeters, the population is 58, and there are 3 survivors. For 9.3 millimeters, the population is 47, and there are 7 survivors. For 9.8 millimeters, the population is 43, and there are 9 survivors. For 10.3 millimeters, the population is 28 and there are 10 survivors. For 10.8 millimeters, the population is 5, and there are 2 survivors. For 11.3 millimeters, the population is 0 birds in both groups. In 1977, medium ground finches on Daphne Major experienced a severe drought. The figure shows the beak depths of the initial population before the drought (red bars) and of the drought survivors (black bars). What do the data show? Select all that apply. The most common beak size of the initial population was 8.8 millimeters. A very small proportion (~5%) of the initial population with this beak size survived. Finches with larger beaks had a survival advantage in the 1977 drought. The most common beak size of the surviving population was 10.3 millimeters. A very small proportion (~5%) of the initial population with this beak size survived. More than one-half of the initial population died during the drought. Request Answer Part D The top figure shows beak sizes of the 1976 finch population before the drought of 1977 (red bars) and after the drought (black bars). The lower figure shows the beak sizes of the offspring of the drought survivors in 1978. What do these figures tell us? A bar chart comparing the number of birds for 9 beak depths before and after the drought in 1977. The number of birds divides into 2 groups: the first one represents the initial population before the drought and the second one represents drought survivors. For the beak depth of 7.3 millimeters, the total amount of the population is 2; the number of survivors is 0. For the beak depth of 7.8 millimeters, the population is 12, and there are 2 survivors. For 8.3 millimeters, the population is 30, and there are 4 survivors, respectively. For 8.8 millimeters, the population is 58, and there are 3 survivors. For 9.3 millimeters, the population is 47, and there are 7 survivors. For 9.8 millimeters, the population is 43, and there are 9 survivors. For 10.3 millimeters, the population is 28 and there are 10 survivors. For 10.8 millimeters, the population is 5, and there are 2 survivors. For 11.3 millimeters, the population is 0 birds in both groups. A bar chart comparing the number of birds for 9 beak depths for the offspring of the drought survivors in 1978. For the beak depths of 7.3 and 7.8 millimeters, the number of birds is approximately 2. For the beak depth of 8.3 millimeters, the number of birds is 6. For the beak depth of 8.8 millimeters, the number of birds is 22. For the beak depth of 9.3 and 9.8 millimeters, the number of birds is 35 and 37 respectively. For the beak depth of 10.3 and 10.8 millimeters, the number of birds is 20 and 17 respectively. For the beak depth of 11.3 millimeters, the number of birds is 3. The top figure shows beak sizes of the 1976 finch population before the drought of 1977 (red bars) and after the drought (black bars). The lower figure shows the beak sizes of the offspring of the drought survivors in 1978. What do these figures tell us? A bar chart comparing the number of birds for 9 beak depths before and after the drought in 1977. The number of birds divides into 2 groups: the first one represents the initial population before the drought and the second one represents drought survivors. For the beak depth of 7.3 millimeters, the total amount of the population is 2; the number of survivors is 0. For the beak depth of 7.8 millimeters, the population is 12, and there are 2 survivors. For 8.3 millimeters, the population is 30, and there are 4 survivors, respectively. For 8.8 millimeters, the population is 58, and there are 3 survivors. For 9.3 millimeters, the population is 47, and there are 7 survivors. For 9.8 millimeters, the population is 43, and there are 9 survivors. For 10.3 millimeters, the population is 28 and there are 10 survivors. For 10.8 millimeters, the population is 5, and there are 2 survivors. For 11.3 millimeters, the population is 0 birds in both groups. A bar chart comparing the number of birds for 9 beak depths for the offspring of the drought survivors in 1978. For the beak depths of 7.3 and 7.8 millimeters, the number of birds is approximately 2. For the beak depth of 8.3 millimeters, the number of birds is 6. For the beak depth of 8.8 millimeters, the number of birds is 22. For the beak depth of 9.3 and 9.8 millimeters, the number of birds is 35 and 37 respectively. For the beak depth of 10.3 and 10.8 millimeters, the number of birds is 20 and 17 respectively. For the beak depth of 11.3 millimeters, the number of birds is 3. The offspring had a smaller range of beak depths--from smallest to largest--than their parents (black bars). The finches that survived the drought (black bars) had offspring with much larger beaks. The overall beak depths of the 1978 offspring population are larger the original 1976 population. In 1978, the offspring population is larger than the initial 1976 population before the drought. Part E The Grants witnessed strong selection during droughts in 1977 and 1985. Compare the two droughts. Select all that apply. In both droughts, small-beaked medium ground finches had the highest survival rates. Both droughts events provided strong natural selection on medium ground finch populations. Both droughts resulted in changes to food sources that favored the survival of some medium ground finches over others. In both droughts, large-beaked medium ground finches had the highest survival rates. Request Answer Part F How did the Grants test their hypothesis that differences in birds' songs can keep different species of finches from breeding with one another? They placed stuffed female finches onto branches to see if males would respond. They recorded birds singing on the island of Daphne Major to see which type of song was sung more often by each species. They observed which birds were mating with each other and listened for the songs the birds were singing. They played the songs of medium ground finches and cactus finches through a loudspeaker to see which species responded to each song. Part G The film defines species as populations whose members don't interbreed. What keeps different Galápagos finch species from mating? Select all that apply. Males only court females that have a similar beak and similar size. Geographic isolation and different environments led to changes in traits that affected mating. Individuals recognize and only respond to songs of their own species. One population eats mostly small, soft seeds and the other population eats mostly large, hard seeds.

A Different finch beak shapes are evidence that finch species adapted to different environments over many generations. B Many years ago, a small population of a single finch species migrated to the islands and evolved into the current 13 species. C The most common beak size of the initial population was 8.8 millimeters. A very small proportion (~5%) of the initial population with this beak size survived. Finches with larger beaks had a survival advantage in the 1977 drought. More than one-half of the initial population died during the drought. D The overall beak depths of the 1978 offspring population are larger the original 1976 population. E Both droughts events provided strong natural selection on medium ground finch populations. Both droughts resulted in changes to food sources that favored the survival of some medium ground finches over others. F They played the songs of medium ground finches and cactus finches through a loudspeaker to see which species responded to each song. G Males only court females that have a similar beak and similar size. Geographic isolation and different environments led to changes in traits that affected mating. Individuals recognize and only respond to songs of their own species.

57 Which of the following is true about XDR-TB? It is not contagious. It is extremely difficult to treat. It causes almost instantaneous death. It has never been recorded in the United States. It is a virus that causes cold-like symptoms. Part B What is true about infection with tuberculosis bacteria? What is true about infection with tuberculosis bacteria? It always results in active disease. It now causes 2 out of every 1000 deaths in the United States. It can cause the gradual destruction of lung tissue. It causes consumption, the overwhelming desire to ingest food. Part C All are true of antibiotics except They are prescribed to combat tuberculosis infection. They are drugs that kill or disable microbes such as bacteria. They can lose their effectiveness when microbes evolve resistance. They are an effective treatment for most cases of the common cold. Part D A population of tuberculosis bacteria can evolve resistance to an antibiotic when the presence of the antibiotic forces the population to change. individual bacteria with the ability to survive in the presence of the antibiotic exist in the population. it is genetically engineered. each cell learns how to disable the antibiotic. Part E What is true about combination drug therapy? It helps to prevent the evolution of resistance in a disease-causing organism. It decreases the likelihood that a single cell or virus becomes resistant to the drug treatment. It has proven effective against HIV infection. Request Answer Provide Feedback

A It is extremely difficult to treat. B It can cause the gradual destruction of lung tissue. C They are an effective treatment for most cases of the common cold. D individual bacteria with the ability to survive in the presence of the antibiotic exist in the population. E It helps to prevent the evolution of resistance in a disease-causing organism. It decreases the likelihood that a single cell or virus becomes resistant to the drug treatment. It has proven effective against HIV infection.

9 Part A The enzyme lactase breaks the sugar lactose into which compound(s)? fructose sucrose glucose galactose Part B How does the term "lactase persistent" relate to the term "lactose tolerant"? A lactase-persistent person is lactose tolerant. Lactose tolerance has nothing to do with lactase-persistence. A lactase-persistent person is lactose intolerant. Part C Four individuals measured their baseline blood glucose, then drank a litre of milk. They then measured their blood glucose levels at regular 15 minute intervals for 60 minutes. The results are shown in the graph below. Which individuals are lactase-persistent? A graph representing dependence of the blood glucose level on time for Peter, Rachel, Sarah, and Arthur. The curve of Sarah starts from the glucose level of 108 milligrams per milliliter, then rises to 141 milligrams per milliliter in 45 minutes, and decreases to 139 milligrams per milliliter in 60 minutes. The curve of Peter starts at the glucose level of 95 milligrams per milliliter, then rises to 153 milligrams per milliliter in 45 minutes, and then falls to 144 milligrams per milliliter in 60 minutes. The curve of Rachel starts at 95 milligrams per milliliter, then increases to 105 milligrams per milliliter in 30 minutes, and decreases to 98 milligrams per milliliter in 60 minutes. The curve of Arthur starts at 95 milligrams per milliliter too, then decreases to 83 milligrams per milliliter in 45 minutes, and rises to 88 milligrams per milliliter in 60 minutes. -Rachel -Sarah -Arthur -Peter Part D What did researchers discover about the genetic mutation causing lactase persistence? It is the same mutation in European and African populations. It is found in the coding region of the lactase gene on chromosome 2. The mutation affects different genes in European and African populations. It is found in a regulatory region (a "switch") upstream of the lactase gene. Part E Which discovery supports the hypothesis that evolution of the lactase-persistence trait was driven by the use of milk in pastoralist cultures? People who are lactase persistent have a mutation in the switch region of the lactase gene. Ancient pots used to hold milk are about the same age as the lactase-persistence mutations. Scientists have discovered different mutations for lactase persistence in different cultures. The lactase gene is present in both humans and domesticated animals. Part F How could milk-drinking have provided strong favorable selection for lactase persistence? Milk was safer to drink than water and reduced exposure to pathogens. Milk may have been a critical food source during times of famine. Milk is protein and fat-rich and therefore could have been an important, high-quality food source. Part G Suppose that a mutation for lactase-persistence occurred in each of the populations described below. In which populations would the mutation be more likely to increase in frequency over time because of natural selection? a population that raises potatoes and chickens a population that raises corn and beans a population that raises rice and tilapia fish a population that raises wheat and sheep

A glucose; galactose B A lactase-persistent person is lactose tolerant. C Sarah; Peter D It is found in a regulatory region (a "switch") upstream of the lactase gene. E Ancient pots used to hold milk are about the same age as the lactase-persistence mutations. F Milk was safer to drink than water and reduced exposure to pathogens. Milk may have been a critical food source during times of famine. Milk is protein and fat-rich and therefore could have been an important, high-quality food source. G a population that raises wheat and sheep

3 Why is combination drug therapy used to treat certain diseases? Fewer side effects may be possible for the patient if more drugs are used at lower dosages. A greater number of microorganisms can be affected if more drugs are used. Possible damage to any particular body organ will be reduced if different drugs are used. A greater number of genetic changes are required for resistance to develop if a greater number of drugs are used.

A greater number of genetic changes are required for resistance to develop if a greater number of drugs are used.

21 Which variation could be subject to natural selection? A tree is not infested by a ground-dwelling beetle when the lower branches are removed. A hyena born with a spotted fur pattern may hide in the grass better than its litter mates. A dog with short legs due to malnutrition may crawl into holes better than his litter mates. A pigeon learns that when its keeper comes near it will get fed.

A hyena born with a spotted fur pattern may hide in the grass better than its litter mates.

8 What situation ensures that natural selection will change a population significantly? At least one individual in the population must develop a new gene in response to an environmental change. The environment should remain relatively stable for a long period of time. Low levels of competition among members of the population should occur. A large number of individuals who are not fit must be eliminated from the population without reproducing.

A large number of individuals who are not fit must be eliminated from the population without reproducing.

2 Which sequence of events describes natural selection? A population of a mammal species lives near the water; water levels rise and the habitat becomes swampy; the animals have trouble moving in the water; the population moves to an area with less water. A population of a mammal species varies in the length of their legs; water levels rise and the habitat becomes swampy; the individuals with shorter legs are better able to swim to food; the population evolves to become shorter-legged. Water levels rise, and a habitat becomes swampy; a population of a mammal species on high ground observes the change; individuals with shorter legs migrate to the area. A population of a mammal species lives near the water; water levels rise and the habitat becomes swampy; the act of swimming shortens the legs of the mammals; the offspring of the mammal species have shorter legs.

A population of a mammal species varies in the length of their legs; water levels rise and the habitat becomes swampy; the individuals with shorter legs are better able to swim to food; the population evolves to become shorter-legged.

65 Part A What mechanism explains the increase in the proportion of flies carrying the allele that increases the rate of alcohol metabolism? chance genetic mutation low levels of alcohol in the environment evolution by natural selection Part B In the high-alcohol environment, individual flies who carried the fast-processing allele had higher fitness than those who did not carry it. What does that mean? Flies with the fast-processing allele were less likely to consume alcohol than the flies without the allele. Flies with the fast-processing allele were more likely to survive and reproduce than the flies without the allele. Flies with the fast-processing allele required less energy to fly than the flies without the allele. Flies with the fast-processing allele were stronger than the flies without the allele.

A. evolution by natural selection B. Flies with the fast-processing allele were more likely to survive and reproduce than the flies without the allele.

46 Which observation is not part of the theory of natural selection? Some variation can be passed on to offspring. All species are descended from a common ancestor. Individuals in a population vary. Populations produce more offspring than the environment can support.

All species are descended from a common ancestor.

56 At what point in the evolution of antibiotic resistance does mutation play a role? After bacteria enter a host but before they start to multiply in the host Before bacteria enter a host After the host takes an antibiotic After bacteria are exposed to the action of the immune system

Before bacteria enter a host

43 Which action would produce a line of horses with long ears? Pull on the ears of horses before mating them. Mate horses with normal ears and look for offspring with long ears. Breed two horses with longer than usual ears. Mate horses in a noisy environment for several generations to promote long ear growth.

Breed two horses with longer than usual ears.

52 Which scientific procedures would provide the best evidence for the theory of natural selection? By finding similarities between modern flowering plants and fossilized ferns By comparing a bacterial population exposed to a factor that kills most organisms over many generations with an unexposed population By observing the human-like behaviors of chimpanzees in social settings By evaluating the genetic changes in an elephant group over many generations relative to the original population

By comparing a bacterial population exposed to a factor that kills most organisms over many generations with an unexposed population

22 Why aren't antibiotics used against the common cold? Antibiotics are only effective if taken immediately after viral infection. Cold viruses have already evolved resistance to antibiotics. Antibiotics are only active against infection in the blood but not the respiratory tract. Colds are caused by viruses that are not affected by antibiotics.

Colds are caused by viruses that are not affected by antibiotics.

11 In what way is artificial selection different from natural selection? Artificial selection only applies to changes in domestic animals rather than wild species. Human preference drives artificial selection rather than changes in environmental conditions. Artificial selection results in a completely new species rather than modifying an existing one. There's no difference; both have caused evolution throughout the history of life on Earth.

Human preference drives artificial selection rather than changes in environmental conditions.

6 What change may occur if a population of fruit flies is exposed to a food source with high-alcohol content? Flies in the population would reproduce more rapidly because of the extra food source. Flies in the population would evolve different mouth parts so they could avoid ingesting the alcohol in the food. Individuals who are not tolerant of the ethanol would die, and individuals who are naturally tolerant would survive. Most flies in the population would develop a mutation that allowed them to process more alcohol.

Individuals who are not tolerant of the ethanol would die, and individuals who are naturally tolerant would survive.

42 Can bacterial resistance to antibiotics be prevented? No: Bacteria need to become resistant to anything that will kill them. Yes: If we stop using antibiotics, the trait will disappear. Yes: If we give antibiotics properly, resistance will go away and not evolve again. No: However, by using antibiotics properly, we can slow the rate at which resistance appears.

No: However, by using antibiotics properly, we can slow the rate at which resistance appears.

19 Why is widespread resistance to tuberculosis (TB) not likely to evolve any time soon? Humans are no longer evolving, so the population cannot develop widespread resistance. TB is highly fatal, so those who are nonresistant will die quickly. Only a small percentage of people who are nonresistant to the bacterium will become infected and die from TB, so the variant will stay in the population. It would be too expensive to genetically engineer people to give them the resistance gene

Only a small percentage of people who are nonresistant to the bacterium will become infected and die from TB, so the variant will stay in the population.

51 Which statement best describes the phenomenon of antibiotic resistance in bacteria? Resistance can be partial or total, and resistance to each antibiotic is a separate trait. When a type of bacteria is resistant to antibiotics, it's resistant to all antibiotics. For a particular antibiotic, all bacteria are either completely resistant or completely sensitive. Resistance to antibiotics developed after pharmaceutical use became common.

Resistance can be partial or total, and resistance to each antibiotic is a separate trait.

63 What is artificial selection? Selection that is quickly reversed when environmental conditions change Selection caused by humans A hypothesis for past selective processes that cannot be tested now Selection that occurs in a laboratory setting

Selection caused by humans

66 You are culturing bacteria from a source that has never been exposed to antibiotics. Could any bacteria in the population have the trait of resistance? The bacteria will either be 100% sensitive or 100% resistant. Some bacteria in the culture may have the trait even without exposure. Antibiotic resistance is a worldwide phenomenon so many bacteria will definitely be resistant. No, without exposure to antibiotics the trait of resistance doesn't occur.

Some bacteria in the culture may have the trait even without exposure.

25 Insecticide spraying greatly reduced the number of gypsy moths in a large city for several years. Over time, the population of gypsy moths slowly increased to a number greater than before the spraying began. Which explanation applies to this situation? The gypsy moths migrated to a new area and returned when the insecticide disappeared. Some gypsy moths were not killed by the insecticide and passed their resistance to offspring. The insecticide caused new mutations for resistance in the surviving moths. Gypsy moths from other areas moved in and replaced the ones killed by the insecticide.

Some gypsy moths were not killed by the insecticide and passed their resistance to offspring.

53 How do bacterial mutations make bacteria resistant to antibiotics? The mutation either disables or counteracts the antibiotic so the bacteria can live in the presence of antibiotics. The mutation causes the bacteria to move to another part of the body where the antibiotic is not present. The mutations change the bacteria to a species that is not killed by the antibiotic. The mutation forces the antibiotic to kill other kinds of bacteria and ignore the mutated bacteria.

The mutation either disables or counteracts the antibiotic so the bacteria can live in the presence of antibiotics.

45 What happens when a population of organisms is evolving? The population improves. The population remains static with no change. The population increases. The population changes over time.

The population changes over time.

41 Part A On average, how much larger was bill depth in this population in 1978 compared to 1976? 0.7 mm 10.2 mm 60 mm It is impossible to determine from the information given. Part B Which of the following statements are supported by the data in this graph? Select all that apply. The population size after the drought was less than 14 of the population size before the drought. In this population, the finches with larger bills had greater fitness than those with smaller bills. The range of bill depths in the population was the same before and after the drought. The likelihood of survival through the drought was equal for birds of all bill depths. Natural selection resulted in a change in average bill depth in this population between 1976 and 1978.

The population size after the drought was less than 14 of the population size before the drought. In this population, the finches with larger bills had greater fitness than those with smaller bills. Natural selection resulted in a change in average bill depth in this population between 1976 and 1978.

30 As natural selection acts on a trait in a population, how will the amount of variation associated with that trait in the population change? Variation will disappear altogether. Variation will remain the same. Variation will decrease. Variation will increase.

Variation will decrease.

24 In spring, the white coat of snowshoe hares will change to brown. How might snowshoe hares be affected by global climate change? With shorter winters, snowshoe hares will remain white in brown environments. With stronger blizzards, snowshoe hares will not turn to brown. Snowshoe hares will drink less water in drier conditions. Snowshoe hares will grow lighter coats for warmer conditions.

With shorter winters, snowshoe hares will remain white in brown environments

33 What is MRSA? a form of skin bacteria that's resistant to methicillin tuberculosis bacteria resistant to antibiotics antibiotics used as a last resort for resistant bacteria any bacteria resistant to antibiotics

a form of skin bacteria that's resistant to methicillin

4 What is combination drug therapy? one drug that has a combination of effects a mixture of several different kinds of drugs given simultaneously a mixture of drugs and homeopathic medications drugs to combat an infection administered in several, successive treatments

a mixture of several different kinds of drugs given simultaneously

18 Which factor would exert the most selection pressure on a population of insects? a fire an earthquake the introduction of a population of feral cats into the area a new species of bird in the area

a new species of bird in the area

16 What causes the disease tuberculosis? genetics a particular type of bacteria a particular type of virus exposure to polluted air

a particular type of bacteria

32 What is an allele? a trait that has been influence by artificial selection a gene that hasn't changed over time a particular version of a gene a gene that has been changed by natural selection

a particular version of a gene

47 How is tuberculosis transmitted? by infected blood products by sneezes by sexual contact by contaminated food

by sneezes

38 Which species has been most affected by artificial selection? Bears Oak trees Cows Mycobacterium tuberculosis

cows

15 To observe how pesticide affects natural selection in a rat population, how much pesticide should be used? enough to kill the weakest 1% of the rats enough to kill most but not all rats enough to kill all the rats just enough so the rats will be exposed but not killed

enough to kill most but not all rats

28 What body part is primarily affected by tuberculosis? lung stomach skin eye

lung

14 What is the primary source for new, unique genes in a population? artificial selection mutation sexual selection random alignment

mutation

60 In a population, which individuals are most likely to survive and reproduce? the individuals who are best adapted to the environment the largest individuals in the group the individuals who can catch the most prey the individuals who grow the most rapidly

the individuals who are best adapted to the environment

59 Which example is an evolutionary adaptation? an apple tree grafted with a pear tree branch webbed feet on a duck immunity to a virus caused by vaccination clipped ears on a dog to prevent ear infections

webbed feet on a duck