Unit 7 - AP Bio

A biologist spent many years researching the rate of evolutionary change in the finch populations of a group of islands. It was determined that the average beak size (both length and mass) of finches in a certain population increased dramatically during an intense drought between 1981 and 1987. During the drought, there was a reduction in the number of plants producing thin-walled seeds. Which of the following best describes the mechanism behind the change in beak size in the finch population?

A change in gene frequencies in the finch population due to selective pressure from the environmental change

Which of the following questions about the origin of life on Earth is most scientifically testable?

Can simple organic molecules form spontaneously in an oxygen-free atmosphere?

The amino acid sequence of cytochrome c is exactly the same in humans and chimpanzees. There is a difference of 13 amino acids between the cytochrome c of humans and dogs, and a difference of 20 amino acids between the cytochrome c of humans and rattlesnakes. Which of the following statements is best supported by these data?

The human is apparently more closely related to the chimpanzee than to the dog or rattlesnake.

All of the following were likely present on the primitive Earth during the evolution of self-replicating molecules EXCEPT

an O2-rich atmosphere

The different species of finches on the Galapagos Islands are believed to have arisen as a result of natural selection acting on populations of finches that had experienced

geographic isolation

All of the following are examples of prezygotic genetic isolating mechanisms EXCEPT:

The progeny of a cross between two different lizard species fail to develop properly.

The fossil record indicates that in some cases reasonably well-defined species appear suddenly and remain unchanged for a long time before they become extinct. This phenomenon is referred to as

punctuated equilibrium

The condition in which there are barriers to successful interbreeding between individuals of different species in the same community is referred to as

reproductive isolation

For following group of questions first study the description of the situation and then choose the one best answer to each question following it and fill in the corresponding oval on the answer sheet. A survey reveals that 25 percent of a population of 1,000 individuals have attached earlobes (are homozygous recessivefor the trait). For the following questions, assume that the population fits the parameters of the Hardy-Weinberg law. What is the frequency of the recessive allele?

sqaure root 0.25

The appearance of a fertile, polyploid individual within a population of diploid organisms is a possible source of a new species. If this individual is capable of reproducing to form a new population, scientists would consider this to be an example of

sympatric speciation

A widely accepted hypothesis about the origin of life on Earth is that life arose approximately 3.5 billion years ago as the result of a complex sequence of chemical reactions that took place spontaneously in Earth's atmosphere. Another hypothesis about the origin of life suggests that life began somewhere else in the universe and arrived on Earth by chance. Which of the following questions might scientists ask to most reliably determine if there has ever been life on Mars?

Did Mars have the elements present in its atmosphere to support life?

Darwin is considered the "father of evolutionary biology." Four of his contributions to the field of evolutionary biology are listed below. The non-constancy of species Branching evolution, which implies the common descent of all species Occurrence of gradual changes in species Natural selection as the mechanism for evolution Darwin's ideas have been enhanced and modified as new knowledge and technologies have become available. Discuss how TWO of the following have modified biologists' interpretation of Darwin's original contributions. Hardy-Weinberg equilibrium Punctuated equilibrium Genetic engineering

FRQ...google the question and the college board rubric will come up

Finch beak depth was measured before and after a severe drought in 1977. The averaged results are shown in Figure 1. After the drought, there were fewer seeds available for the finches to eat and the seeds that did remain were larger and harder to crack open. Researchers claim that when large, hard seeds are the predominate food source, the average beak depth of these finches tends to increase in subsequent generations. Using the evidence provided what is the reaserachers claim ?

Finch beak depth increased as a consequence of selective pressure after the drought because the remaining seeds were larger and harder.

A biologist spent many years researching the rate of evolutionary change in the finch populations of a group of islands. It was determined that the average beak size (both length and mass) of finches in a certain population increased dramatically during an intense drought between 1981 and 1987. During the drought, there was a reduction in the number of plants producing thin-walled seeds. Which of the following statements might best explain the increase in average beak size in the finch population during the drought?

Finches with bigger beaks are better able to crack thick-walled seeds and produce more surviving offspring.

Undersea landslides can disrupt marine habitats by burying organisms that live on the ocean floor. The graph above shows the size of a population of a certain organism that lives on the ocean floor. The population was affected by a recent landslide at the time indicated on the graph. Which of the following best predicts how the population will be affected by the landslide?

The reduced population will likely have allelic frequencies that are different from the initial population.

Two populations of a species of squirrel are geographically isolated from each other. Although they have the same population density, one population is significantly larger in number than the other. A new bacterial disease, which is easily spread and extremely virulent, affects both populations at the same time. Which of the following is the best prediction of how the new disease will affect the two populations?

The smaller population will be more affected than will the larger population, because the smaller population has less genetic variation than the larger population has.

Climate change is disrupting the length of winter in various ecosystems, resulting in less snowfall and milder winters. Scientists in Finland have been observing the tawny owl, a fairly large owl species that is commonly found in woodlands across much of Europe and Asia. Typically, the feathers of the upper body are either brown (BBBB) or gray (bbbb). Scientists studying tawny owls in Finland have found that the percentage of tawny owls that have brown feathers has increased over the past 28 years. Which of the following best explains why the brown-feathered phenotype in tawny owls has increased over the past 28 years?

With milder winters, the advantage of gray feathers that blend into a snowy environment has decreased.

In a small group of people living in a remote area, there is a high incidence of "blue skin", a condition that results from a variation in the structure of hemoglobin. All of the "blue-skinned" residents can trace their ancestry to one couple, who were among the original settlers of this region. The unusually high frequency of "blue skin" in the area is an example of

genetic drift

The wing of a bat, the flipper of a whale, and the forelimb of a horse appear very different, yet detailed studies reveal the presence of the same basic bone pattern. These structures are examples of

homologous structures

A survey reveals that 25 percent of a population of 1,000 individuals have attached earlobes (are homozygous recessivefor the trait). For the following questions, assume that the population fits the parameters of the Hardy-Weinberg law. If p equals the frequency of the dominant allele and q equals the frequency of the recessive allele, which of the following terms represents the frequency of the individuals who show the dominant phenotype?

p2 + 2pq

The other frqs were on paper and she never handed those back. We had to circle the outgroup of the clade and stuff like that.

you should google ap bio unit 7 frqs and a couple samples should come up!