Exam 24: Evolution by Natural Selection

Many crustaceans (e.g.,lobsters,shrimp,and crayfish)use their tails to swim,but crabs have reduced tails that curl under their shells and are not used in swimming.This is an example of

Evolution by natural selection changes the population but not the individual.

Which of the following statements is an example of typological thinking?

Figure 24.2 The distribution of pocket-mouse coat colors in several Arizona populations is associated with substrate color.Some populations live on light-colored granite substrate,and others live on dark volcanic rock.In Figure 24.2,chart A shows the frequency of the melanic (dark)coat phenotype across six populations.Populations C,D,and E live on dark volcanic rock;populations A,B,and F live on light-colored granite.Chart B shows the frequency of the Melanocortin-1 receptor (Mc1r)allele across these populations.The Mc1r alleles,D and d,differ by four amino acids;mice with DD and Dd genotypes have dark coats,whereas mice with dd genotype are light colored.Which of the following statements best interprets the results shown in charts A and B? A)Frequency of the D allele is closely associated with the melanic phenotype,but is unrelated to the presence of dark substrate color. B)Frequency of the D allele is not associated with the melanic phenotype,but is associated with the presence of dark substrate color. C)Frequency of the D allele is closely associated with both the melanic phenotype and the presence of dark substrate color. D)Frequency of the D allele is associated neither with the melanic phenotype nor with the presence of dark substrate color. E)Frequency of the D allele does not vary.

Your text discusses the evolution of antibiotic-resistant M.tuberculosis bacteria in a patient.Researchers discovered that the strain of M.tuberculosis taken from the dead patient has a point mutation in the rpoB gene that codes for part of the RNA polymerase enzyme.This mutant form of RNA polymerase does not normally function as well as the more common form,but a commonly used antibiotic called rifampin does not affect the mutant rpoB.A researcher places M.tuberculosis isolated from the patient a year before death (no rpoB mutation)in cell cultures with M.tuberculosis isolated from the dead patient (with rpoB mutation).Half the cell cultures contain just standard nutrients,and the other cell cultures contain rifampin in addition to the standard nutrients.After many cell generations,the researcher finds that

According to the theory of evolution by natural selection,which of the following is FALSE?

If the population is maintained on media that contains rifampin,what is expected to occur over a period of time?

Which of the following is the best modern definition of evolution?

Which of these conditions are always true of populations evolving due to natural selection? Condition 1: The population must vary in traits that are heritable. Condition 2: Some heritable traits must increase reproductive success. Condition 3: Individuals pass on all traits they acquire during their lifetime.

Who proposed that organisms could be organized into a great chain of being?

A population of rabbits grows explosively because resources are high.However,now that numbers have increased substantially,there is not enough food for all individuals and the population is threatened.What will happen under such circumstances?

Why was Darwin and Wallace's theory of evolution by natural selection revolutionary?

Evolutionary theory predicts that species are related,not independent.Four of the following examples provide support for this prediction,but one is irrelevant.Which one of these examples does not support the claim that species are related?

Claytonia virginica is a woodland spring herb with flowers that vary from white to pale pink to bright pink.This plant is primarily pollinated by a bee that prefers pink flowers to white flowers.Claytonia with pink flowers have a greater relative fruit set than Claytonia with white flowers.Nevertheless,the percentage of different flower colors remains stable in the study population from year to year.Which of these statements might explain this observation?

Consider gene A,which has two (2)alleles in the population.A₄ codes for a mutated allele,which does not produce any protein;the associated phenotype is a disease state that reduces reproductive ability.A₂ is the normal allele and is dominant to the phenotype of A₄;the associated phenotype is not diseased.Based on this information,can natural selection eliminate the A₄ allele?

A farmer uses triazine herbicide to control pigweed in his field.For the first few years,the triazine works well and almost all the pigweed dies;but after several years,the farmer sees more and more pigweed,no matter how often he applies triazine.Which of these actions is most likely to solve the farmer's problem?

Why did Darwin argue that evidence of extinction supports the theory of evolution?

Radiometric dating is a technique used to determine the age of rocks.Geologists have used this technique to determine that

Evolution of antibiotic resistant bacteria represents which of the following?

A population of beetles lives on a forest floor,which is covered in dark leaf litter.Dark beetles have the genotype A₂A₂,while lighter beetles have an A₁A₁ genotype;heterozygotes have a phenotype that is closer to that of the A1A1 homozygotes.The oppresso bird preys on these beetles.What do you predict will be the outcome of this predation over time?