SCI 2020 HW 11

(Drug Resistance) Part A: Has evolution by natural selection recently occurred in the worldwide populations of Mycobacterium tuberculosis?

Yes, the frequency of the adaptive allele for drug resistance has increased over time.

(Bacteria Evolve) Part A: Which of the following is necessary for a new protein to be produced in a cell?

a mutation

(An Evolving Enemy) Part F: Which of the following is the best definition of adaptation?

a trait favored by natural selection

(Natural Selection) Part B: Which of the following statements are supported by the data in this graph?

-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. -The population size after the drought was less than 1/4 of the population size before the drought.

(Sickle Cell) Part D: If a person has two normal copies of the hemoglobin allele, which statements are true?

-The person is homozygous at the hemoglobin locus. -The person is susceptible to malaria.

(Natural Selection) Part A: On average, how much larger was bill depth in this population in 1978 compared to 1976?

0.7 mm

(Human Family Tree) Part A: Which of the following specimens discovered in 1972 ignited the debate about multiple lineages within the genus Homo?

1470

(New Antibiotic) Part D: If teixobactin remains unchanged and works in humans as in mice, which of the following individuals would be most likely to receive it?

A 27 year old woman with a staph infection

(New Antibiotic) Part B: You are part of a team of doctors doing a Phase 2 study of teixobactin on humans. Assuming protocol had not changed since the mice study, how are you administering the drug?

By injection

(Antibiotics Use) Part E: Which of the following is true?

Countries besides the U.S. have legislation in place regarding the use of antibiotics in livestock.

(Three Modes) Part A: In a species of snail, dark-shelled individuals are better hidden from bird predators in the shady forest, while light-shelled individuals are better hidden in well-lit brushy edge areas. If there were no areas of intermediate brightness in this habitat, which type of selection would act on shell color in these snails?

Disruptive selection

(An Evolving Enemy) Part E: With proper care, all the offspring in a generation will survive

False

(Sickle Cell) Part E: In some populations, 1 in 500 people have sickle cell disease. What reason does the film give for why a potentially deadly, inherited disease is found at such high frequencies?

Individuals with one sickle cell allele are protected from malaria and do not have sickle cell disease, thus keeping the allele in the population.

(New Antibiotic) Part E: You are a microbiologist working for the drug company GlaxoSmithKline. You discover a potential new antibiotic that works in the same fashion as teixobactin. How does it work?

It prevents bacteria from building cell walls.

(Lactose Intolerance) Part B: Why is the enzyme lactase necessary to digest dairy products?

Lactase breaks down lactose into smaller molecules that can be absorbed by the cells that line the small intestine.

(Lactose Intolerance) Part F: Most people are lactose intolerant as adults, but nearly everyone produces sufficient lactase as an infant. However, in some cases, genetic mutations can occur that make an infant lactose intolerant. From an evolutionary perspective -- over thousands of years -- why would lactose intolerance in infants be very rare in the population?

Lactose intolerant infants could not digest breast milk and therefore usually died, never having the chance to pass the mutation on to their children.

(New Antibiotic) Part C: Which of the following is true?

Most known bacteria will not grow under normal lab conditions.

(Sickle Cell) Part A: Compare sickle cell disease and malaria.

Sickle cell disease and malaria are both potentially lethal diseases.

(Three Modes) Part B: Small lizards have difficulty defending their territory, but large lizards are more likely to be preyed upon by owls. Which type of selection would act on body size in these lizards under these conditions?

Stabilizing selection

(Antibiotics Use) Part C: Which of the following people is most likely to be against the new antibiotics legislation?

The CEO of the National Pork Producers Council.

(Antibiotics Use) Part D: Which of the following prompted the passing of the new legislation regarding antibiotic use in livestock?

The decreasing effectiveness of antibiotics in humans.

(Lactose Intolerance) Part E: In which country would you most likely find a higher incidence of lactase persistence?

in a Scandinavian country where people historically raised dairy cattle and made cheese

(Human Family Tree) Part B: You are a researcher working closely with the Leakey family, studying the newly discovered fossils to determine their place in the human lineage. Which of the following are you?

paleoanthropologist

(Bacteria Evolve) Part C: What controls genes?

proteins

(An Evolving Enemy) Part A: In natural selection, what changes in a population over time?

the frequency of an allele for a particular gene in a population

(Human Family Tree) Part D: Which of the following is the closest relative to Homo sapiens?

the orangutan, a great ape

(An Evolving Enemy) Part B: What do alleles give rise to in a population?

variation

(Sickle Cell) Part C: How did Dr. Allison test his hypothesis that sickle cell disease was connected to malaria?

-He evaluated blood samples for malaria parasites and the presence of sickle cells. -He expanded his study area beyond Kenya to the rest of East Africa to see if malaria and sickle disease were connected.

(Sickle Cell) Part F: How does Dr. Allison's work provide an example of natural selection in humans?

-In areas without malaria, individuals with two sickle cell alleles reproduced at lower rates than those without sickle cell disease. -In areas with malaria, individuals with one sickle cell allele reproduced at higher rates than those with no sickle cell alleles.

(Lactose Intolerance) Part A: Why should we not view lactose intolerance as a disease in adult humans?

Adult humans did not consume dairy products until fairly recently in our evolutionary history.

(An Evolving Enemy) Part G: In any population, the odds of surviving are due to chance.

Flase

(Antibiotics Use) Part A: You are a cattle rancher and will abide by the new legislation. Which of the following will you be allowed to do?

Give antibiotics to an animal in your herd that is ill.

(Sickle Cell) Part B: In 1949, Dr. Tony Allison observed a high frequency of Kenyans carrying the sickle cell allele in coastal areas and near Lake Victoria, but a lower frequency in the highlands. What did he hypothesize?

He hypothesized that there was a connection between malaria and sickle cell disease.

(Human Family Tree) Part C: You discover the skull of a species very similar to 1470. Which of the following two species is it most like?

Homo habilis and Homo rudolfensis

(Bacteria Evolve) Part E: You are an epidemiologist working to stop fast moving bacterial infection in which bacteria behave in nature like Pseudomonas aeruginosa. Which of the following would be the best for you to figure out?

How to break through their biofilm shield.

(Human Family Tree) Part E: Which of the following do most biologists currently think is true?

Human evolution followed a path with many branches.

(Drug Resistance) Part C: In the United States today, about half of the corn crop is genetically engineered with a protein that is toxic to corn borers, an insect pest of corn. Which of the following conditions would be necessary for the corn borer to evolve resistance to the toxic protein?

The corn borer must have heritable variation in resistance to the toxic protein. The resistant corn borers must survive better or reproduce more than nonresistant corn borers.

(Drug Resistance) Part B: Which of the following statements describes the adaptation that Mycobacterium tuberculosis bacteria have evolved in response to their new environment?

The drug-resistance trait is an adaptation to the environment in which human hosts are medicated with the antibiotic rifampin.

(Sickle Cell) Part G: Predict what will happen to the frequency of the sickle cell allele in areas where malaria has been eradicated.

The sickle cell allele will decrease in frequency.

(Lactose Intolerance) Part C: How do lactase supplements help people who are lactose intolerant?

The supplements provide the enzyme that breaks down the lactose in dairy products.

(New Antibiotic) Part A: If teixobactin works in humans as it did in mice, which of the following will be true?

There will be no side effects

(Bacteria Evolve) Part B: You are a bacteriologist studying reproduction. Why is Pseudomonas aeruginosa a good choice for your research?

They live virtually everywhere

(Antibiotics Use) Part B: What does the FDA think drug companies will do regarding voluntary label changes on antibiotics for livestock?

They will comply with the new recommendations.

(Bacteria Evolve) Part D: What was the advantage for Pseudomonas aeruginosa to have many tails?

To get to food more quickly

(Lactose Intolerance) Part G: Lactose intolerance in infants is more common in the population today than it was a hundred years ago. Why?

Today there are alternatives to breast milk, such as lactose-free formula and soy milk, so lactose intolerant infants can survive.

(An Evolving Enemy) Part C: You can observe that at least some traits pass from parent to offspring.

True

(An Evolving Enemy) Part D: You can observe that members of a biological population differ from one another.

True

(Lactose Intolerance) Part D: When should a lactase supplement be taken in order to be most effective, and why?

at the same time the dairy product is consumed, so that the lactase will be in contact with the lactose

(An Evolving Enemy) Part H: Your aunt's garden has a mix of native plants. Of the yellow coneflowers growing this year, some have shallow roots that extend only 4 or 5 inches below the surface. Others have roots that extend 10 to 12 inches below the surface. Severe drought, that is, lack of precipitation, afflicts your aunt's region for 6 months. Now, based on common knowledge and your understanding of natural selection, which kind of yellow coneflower will there be more of next year in your aunt's garden?

deep-rooted plants