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Microevolution and the
Genetics of Populations
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Printed: January 1, 2015
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C HAPTER
Chapter 1. Microevolution and the Genetics of Populations
1
Microevolution and the
Genetics of Populations
Lesson Quiz
Name___________________ Class______________ Date________
Multiple Choice
Circle the letter of the correct choice.
1. The conditions for Hardy-Weinberg equilibrium include that
a.
b.
c.
d.
only a few individuals move into or out of the population.
no new alleles are being created.
non-random mating is occurring.
all of the above
2. Which statement best describes directional selection?
a. Directional selection occurs when phenotypes at both extremes of the phenotypic distribution are selected
against.
b. Directional selection occurs when one of two extreme phenotypes is selected against.
c. Directional selection occurs when one of two extreme phenotypes is selected for.
d. Directional selection occurs when phenotypes in the middle of the range are selected against.
3. Which statement is correct concerning natural selection?
a.
b.
c.
d.
Natural selection occurs when there are differences in fitness among members of a population.
Natural selection occurs when there are differences in gene flow among members of a population.
Natural selection occurs when there are differences in genetic drift among members of a population.
all of the above
4. Gene flow
a.
b.
c.
d.
occurs when individuals move into or out of a population.
must not occur for a population to be at Hardy-Weinberg equilibrium.
is a force of evolution.
all of the above
5. Genetic drift
a.
b.
c.
d.
can occur due to the bottleneck effect, when a few individuals start a new population.
can occur due to the bottleneck effect, which may happen after a forest fire.
can occur due to the founder effect, which may happen after a forest fire.
is the non-random change in allele frequencies that occurs in a small population.
6. Mutations
a.
b.
c.
d.
have a great effect on allele frequencies.
can always be passed to offspring.
are how all new alleles first arise.
all of the above
7. The main difference between macroevolution and microevolution is
1
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a.
b.
c.
d.
the species that evolve during each.
the time frame of the evolutionary process.
that microevolution is only for small organisms, and macroevolution is for large organisms.
all of the above.
8. In a population with 200 members, the total number of copies of each gene in the population is
a.
b.
c.
d.
100.
200.
300.
400.
9. In a population with 200 members, if there are 300 dominant alleles, how many recessive alleles are there?
a.
b.
c.
d.
25
50
100
200
10. In a population with 100 members, if 81 individuals are homozygous dominant, how many individuals have
the recessive phenotype?
a.
b.
c.
d.
1
2
18
19
True or False
Write true if the statement is true or false if the statement is false.
_______ 11. Microevolution occurs over a relatively long period of time within a population.
_______ 12. Allele frequency refers to how often a gene occurs in a population.
_______ 13. Genetic drift occurs when people move into or out of a population.
_______ 14. Stabilizing selection occurs when phenotypes at both extremes of the phenotypic distribution are
selected against.
_______ 15. The founder effect can result in severe genetic phenotypes.
_______ 16. Darwin knew that heritable variations are needed for evolution to occur.
_______ 17. Darwin knew about Mendel’s laws of genetics and inheritance.
Fill in the Blanks
Fill in the blank with the term that best completes the sentence.
18. ____________ occurs over geologic time above the level of the species.
19. ____________ selection occurs when there are differences in fitness among members of a population.
20. The founder effect is prevalent among the ____________ population in the U.S. and Canada.
21. A ____________ effect occurs when a population suddenly gets much smaller.
22. The ____________ consists of all the genes of all the members of the population.
23. Evolution occurs in a population when allele ____________ change over time.
24. Gene ____________ occurs when people move into or out of a population.
25. ____________ selection occurs when phenotypes in the middle of the range are selected against.
Short Answer
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Chapter 1. Microevolution and the Genetics of Populations
Answer each question in the space provided.
26. Hardy and Weinberg used mathematics to describe an equilibrium population (p = frequency of allele A, q =
frequency of allele a): p2 + 2pq + q2 = 1. If p = 0.4, what is the frequency of the AA genotype?
27. Explain why the conditions for Hardy-Weinberg equilibrium are unlikely to be met in real populations.
3