AP Biology: Unit 4 Homework
* adapted from the version by Ms. Foglia
Chapter 22
1. What contemporary of Charles Darwin’s influenced him to finally publish his book? How
did he do this?
2. What were the major points made in The Origin of Species?
3. What were the conventional paradigms in the 1800s when Darwin developed his
theories?
4. What was the contribution of Carolus Linnaeus to the evolutionary theories?
5. How did the study of fossils help Darwin shape his theories?
6. How did geological gradualism and uniformitarianism influence Darwin?
7. Identify the two principles of Lamarck’s theory of evolution.
8. How did the observations during his voyage on the Beagle influence Darwin’s theories?
9. Why were the Galapagos Islands so important to Darwin’s observations?
10. What are the elements for the formation of a new species?
11. What is the driving force behind the evolution of the 14 species of finches on the
Galapagos?
12. Define descent with modification.
13. How does the “tree analogy” represent the evolutionary relationships of creatures?
14. Summarize the 4 observations and 2 inferences recognized as the backbone of evolution
by natural section.
15. How did Darwin’s experience with artificial selection influence his theories of evolution?
16. For each of the following, indicate how it is used as evidence of evolution by natural
selection: paleontology, biogeography, resistance to insecticides, drug resistance,
homology, homologous structures, vestigial organs, embryology, biochemical similarity
Chapter 23
1. Define each of the terms commonly used in population genetics: population, gene pool,
gene frequency
2. List the five conditions that must be met by a population to insure stability (no evolution).
3. Assuming Hardy-Weinberg distribution of genes in a population, write the equation that
describes genotype frequencies.
4. Define the following: p, q, p2, 2pq, q2
5. In a population of wildflowers, p=0.8 and q=0.2. Determine genotype frequencies.
6. In Drosophila, the allele for normal length wings is dominant over the allele for vestigial
wings. In a population of 1,000 individuals, 160 of them show the recessive phenotype.
Determine allele and genotypes frequencies.
7. The allele for the hair pattern called “widow’s peak” is dominant over the allele for no
“widow’s peak.” In a population of 1,000 individuals, 360 of them show the dominant
phenotype. Determine allele and genotype frequencies.
8. What is the Hardy-Weinberg assumption that is broken when genetic drift occurs?
Explain.
9. How does genetic drift apply to the following (be sure to give an example of each):
founder’s effect, bottleneck effect
10. How do each of the following break Hardy-Weinberg assumptions: natural selection,
gene flow, mutation, selective mating
11. Why is genetic variation important to evolution?
12. How can populations vary along a geographic axis compared to isolated populations?
13. What is the role of mutations to forming variation?
14. What factors of sexual reproduction lead to variations within a population?
15. How does diploidy preserve variation?
16. What is “balanced selection”?
17. In a biological sense, what is fitness?
18. Describe or draw the graphs of the three modes of selection: directional, disruptive and
stabilizing selection
19. What is the effect of sexual selection?
20. For each of the following, give an example or describe what is meant by the statement:
(a) natural selection cannot fashion perfect organisms
(b) evolution is limited by historical constraints
(c) adaptations are often compromises
(d) not all evolution is adaptive
(e) selection can only edit existing variations
Chapter 24 and Chapter 25
1. Define species.
2. What is thought to be essential for the formation of distinct species rather than a
continuum from one life to another?
3. Define and give an example for each of the following barriers that cause isolation:
prezygotic barriers, habitat isolation, behavioral isolation, temporal isolation, mechanical
isolation, gametic isolation, postzygotic barriers, reduced hybrid viability, reduced hybrid
fertility, hybrid breakdown
4. Define the modes of speciation: allopatric speciation, sympatric speciation
5. How do island chains encourage adaptive radiation?
6. What are the two intrinsic factors that result in sympatric speciation?
7. How can polyploidy lead to speciation?
8. Why are allopolyploid hybrids usually sterile?
9. Compare and contrast the following: gradualism and punctuated equilibrium,
microevolution and macroevolution
10. What does the range of eye complexity in mollusks demonstrate?
11. What does the evolution of the horse demonstrate?
12. What is convergent evolution?
13. What is phylogeny?
14. How are fossils significant to our study of biology?
15. Describe the meaning of the following statements:
(a) sedimentary rocks are the richest source of fossils
(b) paleontologists use a variety of methods to date fossils
(c) the fossil record is a substantial, but incomplete, chronicle of evolutionary history
(d) phylogeny has a biogeographic basis in continental drift
(e) the history of life is punctuated by mass extinctions
16. What techniques do relative dating use to place fossils in their place in geologic time?
17. What marks the separation between the major eras in the geologic time scale
18. How does absolute dating compare to relative dating?
19. What were the conditions like on early earth that made the origin of life possible?
20. Describe Miller and Urey’s experiment.
21. What are protobionts?
22. What was likely the first genetic material? Why?
23. How was oxygen first introduced into early Earth’s atmosphere?
24. How did the first eukaryotes evolve? Be sure to include the origin of plant and animal
cells in your answer
25. How did multicellularity evolve?
26. When did organisms start moving onto land? How did they survive?
27. What are homeotic genes?