AP Biology Free-Response Week 14 (November 10, 2008)

Use the tips for answering free response questions found on the FSHS AP Biology website. Each question should be answered in essay form with complete sentences and labeled clearly. After completing answer, use a highlighter to emphasize main points and clarifying details of your response. Your free response questions will comprise a major test grade each nine weeks.

1. Sickle-cell disease is caused by a recessive allele. Roughly one out of every 400 African-Americans (0.25%) is afflicted with sickle-cell disease. Use the Hardy-Weinberg equation to calculate the percentage of African-Americans who are carriers of the sickle-cell allele. (Hint: q²=0.0025)

2. The red wolf, Canis rufus, once widespread in the southeastern and south central United States, nearly became extinct in the late 1970s. Saved by a captive breeding program under the authority of the Endangered Species Act (ESA), it has been reintroduced in areas such as the Great Smoky Mountains National Park. Recent genetic evidence indicates that the red wolf may not be a separate species, but a hybrid of the coyote, Canis latrans, and the gray wolf, Canis lupus. Though the original intent of the ESA was to protect all endangered groups-whether species, subspecies or hybrids—the costs may be prohibitive.

  1. What criteria should be applied if we must decide which organisms to protect?
  2. Are there reasons to preserve hybrids, subspecies or local populations when the species as a whole is not at risk?

3.Explain how each of the following makes it difficult to clearly define a species: variation within a species, geographically isolated populations, asexual species, fossil organisms.

4. The problems of survival of animals on land are very different from those of survival of animals in an aquatic environment. Describe four problems associated with animal survival in terrestrial environments but not in aquatic environments. For each problem, explain an evolutionary solution.

5. Organisms differ from one another and yet share characteristics.

  1. Select three kingdoms and briefly describe three characteristics that distinguish between members of one kingdom and members of the other.
  2. Describe three characteristics (at least one molecular and one cellular) that members of these kingdoms share.
  3. Propose an explanation for the existence of similarities and differences between the two kingdoms.