Genetics Exam #1: September 12, 2012
Clearly write your name, student ID # (leave the last space blank) and fill in Test form ‘A’ on your scantron
along with an answer for each question. Write your name on the exam and turn it in with your completed
scantron. You may use a calculator; no cell phones allowed.
TRUE/FALSE. Write ‘A’ if the statement is true and ‘B’ if the statement is false.
1. Gene duplications provide an explanation for the origin of gene families.
2. In eukaryotic cells, the nuclear membrane disappears during the interphase period of the cell cycle.
3. During meiosis, genetic recombination results from crossing over between non-sister chromatids of a pair
of non-homologous chromosomes.
4. Half of the daughters of a man with an autosomal recessive allele will inherit the associated trait.
5. All the sons of a woman with an X-linked dominant allele will inherit the associated trait.
6. About 10% of human genes vary in their copy number.
7. With incomplete dominance, the heterozygous phenotype is expected to show distinct expression of both
8. A person with type O blood could safely receive a blood transfusion of type AB blood.
9. Genetic recombination is the sole source of genetic variation from one human generation to the next.
10. Dominant mutations in the FBN1 gene cause a pleiotropic phenotype known as Marfan syndrome. What
is the normal function of the fibrillin protein that is encoded by the FBN1 gene?
A. Contributes to the structure of connective tissue throughout the body
B. Transports chloride ions through the plasma membrane
C. RNA-binding protein in the brain
D. Promotes growth during fetal development
11. A couple with I I and I I genotypes and one wild-type copy each of the FUT1 gene have children. What
is the probability that a child will have an A blood type phenotype?
12. Mendel studied two contrasting forms of a trait affecting pea pod shape: a dominant inflated pod (I) and
a recessive constricted pod (i). If a test cross of plants with inflated pods to those with constricted pods
resulted in all the 1 plants producing inflated pods, what could you conclude was the genotype of the
parental plant with inflated pods?
A. homozygous for the I allele
B. heterozygous for the I and i alleles
C. homozygous for the i allele
13. After puberty, a healthy male can be expected to produce how many sperm from (a) 100 primary
spermatocytes and (b) 100 secondary spermatocytes?
A. (a) 400 (b) 400
B. (a) 400 (b) 200
C. (a) 200 (b) 100
D. (a) 100 (b) 100
E. (a) 100 (b) 50 Name ____________________________________________
14. Which individuals in the pedigree shown have inherited great-grandfather’s mitochondrial genome?
E. None of the above
15. For the following pedigree, choose the mode of inheritance that is the best fit.
A. Autosomal recessive
B. Autosomal dominant
C. X-linked recessive
D. X-linked dominant
16. A man was recently diagnosed with Huntington’s disease. What is the probability that he inherited this
disease from his mother?
17. A woman and her husband are both heterozygous for the mutant beta-globin allele. What is the
probability that none of their three children will develop sickle-cell anemia?
18. An ovum produced from a first-division chromosomal non-disjunction during meiosis could cause which
of the following disorders:
A. Swyer syndrome
B. Edwards syndrome
C. Fragile X syndrome
D. Chronic myelogenious leukemia
E. XYY individuals
19. Recessive mutations in either of two genes, eyeless (ey) or eyes absent (eya), are known to cause flies
without eyes. In a genetic screen, you find a fly without eyes and wonder if you’ve found a new eye mutant.
If a test cross of your unknown fly to the ey homozygous mutant results in flies missing eyes in the F1
generation, what can you conclude?
A. Mutations in the ey gene cause the mutant phenotype of your unknown fly.
B. Mutations in the ey gene do not cause the mutant phenotype of your unknown fly.
C. Mutations in the eya gene cause the mutant phenotype of your unknown fly.
D. Mutations in the eya gene do not cause the mutant phenotype of your unknown fly.
E. Mutations in a new gene cause the mutant phenotype of your unknown fly.
20. If a tiger sperm cell has 19 chromosomes, how many chromosomes are expected in the zygote?
B. 38 Name ____________________________________________
21. Which of the following types of genetic variation is known to affect the progression of prostate cancer?
A. Reciprocal chromosomal translocation