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Bio 211
3.28.7
Practice Exam IIIc
1. According to Mendel’s law of segregation,
a. There is a 50% probability that a gamete will get a dominant allele
b. Gene pairs segregate independently of other genes in gamete formation
c. Allele pairs separate in gamete formation
d. The laws of probability determine gamete formation
e. There is a 3:1 ratio in the F2 generation
2. A 1:1 phenotypic ration in a testcross indicates that
a. The alleles are dominant
b. One parent must have been homozygous recessive
c. The dominant phenotype parent was a heterozygote
d. The alleles segregate independently
e. The alleles are co-dominant
3. If both parents are carriers of a lethal recessive gene, the probability that their
child will inherit and express the disorder is
a. 1/8
b. ¼
c. ½
d. ½ x ½ x ¼ or 1/16
e. 2/3 x 2/3 x ¼ or 1/9
4. In a dihybrid cross of heterozygote, what proportion of the offspring will be
phenotypically dominant for both traits?
a. 1/16
b. 3/16
c. ¼
d. 9/16
e. ¾
5. You think that two alleles for coat color in mice show incomplete dominance.
What is the best and simplest cross to perform in order to support your
hypothesis?
a. A testcross of a homozygous recessive mouse with a mouse of unknown
genotype
b. A cross of F1 mice to look for a 1:2:1 ration the offspring
c. A reciprocal cross in which the sex of the mice of each coat color is
reversed
d. A cross between two true-breeding mice of different colors to look for an
intermediate phenotype in the F1
e. A cross of F1 mice to look for a 9:7 ratio in the offspring
6. What are autosomes?
a. Sex chromosomes
b. Chromosomes that occur singly
c. Chromosomal abnormalities that result in genetic defects
d. Chromosomes found in mitochondria and chloroplasts
e. None of the above
7. Which of the following is not a source of genetic variation in sexually
reproducing organisms?
a. Crossing over
Bio 211
3.28.7
Practice Exam IIIc
b. Replication of DNA during S phase before Meiosis I
c. Independent assortment of chromosomes
d. Random fertilization of games
e. Mutations
8. Meiosis II is similar to mitosis because
a. Sister chromatids separate
b. Homologous chromosomes separate
c. DNA replication precedes the division
d. They both take the same amount of time
e. Haploid cells are produced
9. Homologous chromosomes
a. Have identical genes
b. Have genes for the same traits at the same loci
c. Are found in gametes
d. Separate in Meiosis II
e. Have all of the above characteristics
10. If a populations has the following genotype frequencies, AA = .42; Aa = .46; aa =
.12; what are the allele frequencies?
a. A = .42; a = .12
b. A = .6; a = .4
c. A = .65; a = .35
d. A = .76; a = .24
e. A = .88; a = .12
11. In a population with two alleles, B and b, the allele frequency of b is .4. What
would the frequency of heterozygotes be if the population was in HardyWeinberg equilibrium?
a. .16
b. .24
c. .48
d. .6
e. You cannot tell from this information
12. Darwinian fitness is a measure of
a. Survival
b. Number of matings
c. Adaptation to the environment
d. Successful competition for resources
e. Number of viable offspring
13. In a study of a population of field mice, you find that 48% of mice have a coat
color that indicates that they are heterozygous for long tails. What would be the
frequency of the dominant allele in the population?
a. .24
b. .48
c. .50
d. .60
e. You cannot estimate allele frequency from this information