Download Chap 23 test with answers-retake

Chapter 23 Quiz-Retake
Name:
Hour:
Fill in the blank with the best answer: Each is worth 2 points (10 Total)
1) _______________ is the accumulation of heritable changes within populations over
time.
Answer: Evolution
2) The physical expression of a trait (e.g., height or eye color) describes an organism’s
_______.
Answer: phenotype
3) ___________ occurs when different phenotypes of the same species survive and
reproduce at different frequencies because some are better adapted to a particular
environment .
Answer: natural selection
4) A population that is not changing (i.e., it has constant genotype and allele frequencies
Answer: equilibrium
5) _________ selection occurs when one extreme of a population contributes more
offspring to the next generation than average members of the population do.
Answer: Directional
Multiple Choice: Circle the best possible answer Each is worth 2 points (12 total)
6. Assume that a population is in Hardy–Weinberg equilibrium for a trait controlled by
one locus and two alleles. If the frequency of the recessive allele is 0.55, what is the
frequency of the dominant allele?
a. 0.50
b. 0.45
c. 0.81
d. 0.19
Answer: B
7. There is a gene that causes people to have crumbly earwax. This gene is expressed as a
complete dominant: Individuals who are homozygous dominants (CC) or heterozygous
(Cc) have crumbly earwax. Homozygous recessives (cc) have gooey earwax. On Paradise
Island there are 100 people, 75 of whom have crumbly earwax. Assuming Hardy–
Weinberg conditions, what is the frequency of the c allele on Paradise Island?
a. 0.25
b. 0.50
c. 0.87
d. None of the above
e. This cannot be answered without more information.
Answer: b
8. Which of the following agents of evolution adapts a population to its environment?
a. Nonrandom mating
b. Natural selection
c. Migration
d. Genetic drift
e. Mutation
Answer: b
9) In the Hardy–Weinberg equation, the heterozygous individuals in a population are
represented by
a. p2.
b. 2pq.
c. q2.
d. p.
e. q.
Answer: b
10. Which of the following populations would demonstrate a population bottleneck?
a. The population of El Paso, Texas, after it has moved in its entirety to Patagonia
b. Eight male and eight female elephant seals that have survived the wreck of the Exxon
Valdez
c. A million male orangutans
d. Six male orangutans collected from a natural population in Sumatra and moved to the
San Diego Zoo
e. None of the above
Answer: b
12. In the Hardy–Weinberg equation, the homozygous recessive individuals in a
population are represented by
a. p2.
b. 2pq.
c. q2.
d. p.
e. q.
Answer: c
Problems: Each is worth 4 points (16 points total). CIRCLE YOUR FINAL
ANSWERS!!
13. The allele for attached earlobes is recessive to the allele for unattached earlobes. In a
poplulation of 1000 people, 750 show the dominant phenotype. What is the frequency of
the recessive allele in this population?
14. Mating behavior in honeybees is a simple dominant, recessive situation. In a
population of 600 honeybees, 504 show the dominant phenotype for mating behavior.
How many show the recessive phenotype of mating behavior and what is the frequency
of the recessive allele in the population of 600.
15. In a certain population, the dominant phenotype occurs 64% of the time. What is the
frequency of the homozygous dominant and heterozygous in the population?
16. Not being able to taste the test paper used in class is recessive to being able to taste it.
So being a non-taster is the recessive phenotype. If 36 out of 100 people could not taste
the test paper, what is the frequencies of heterozygous tasters, homozygous tasters as well
as the frequencies of the p and q alleles?