Download Practice Exam 3- 4/3 Below are sample questions from your book, a

Practice Exam 3- 4/3
Below are sample questions from your book, a student study guide, and some that I made up. These are not
necessarily indicative of the specific material or types of questions that Dr. Roe will ask. Remember, he wants
you to be able to apply your knowledge and material learned in class so make sure that you can answer these and
understand the significance/importance/application of them. Below is also a list of the main categories we
discussed in class that you should know. Good luck!
You Should Know:
 The Cell Cycle/ Mitosis
 Meiosis
 Punnett Squares
 Chromosomal Basis of Inheritance
o Different methods of inheritance
o Dependent vs. independent assortment
o Mendelian vs. non-Mendelian inheritance
 Vocabulary words (check the last page of this exam for a sampling of vocab words)
1. Through a microscope, you can see a cell plate beginning to develop across the middle of a cell and
nuclei re-forming on either side of the cell plate. This cell is most likely
a. an animal cell in the process of cytokinesis
b. a plant cell in the process of cytokinesis
c. an animal cell in the S phase of the cell cycle
d. a bacterial cell dividing
e. a plant cell in metaphase
2. A particular cell has half as much DNA as some other cells in a mitotically active tissue. The cell in
question is most likely in
a. G1
b. G2
c. prophase
d. metaphase
e. anaphase
3. One difference between cancer cells and normal cells is that cancer cells
a. are unable to synthesize DNA
b. are arrested at the S phase of the cell cycle
c. continue to divide even when they are tightly packed together
d. cannot function properly because they are affected by density-dependent inhibition
e. are always in the M phase of the cell cycle
4. In the cells of some organisms, mitosis occurs without cytokinesis. This will result in
a. cells with more than one nucleus
b. cells that are unusually small
c. cells lacking nuclei
d. destruction of chromosomes
e. cell cycles lacking an S phase
5. Which of the following does not occur during mitosis?
a. condensation of the chromosomes
b. replication of the DNA
c. separation of sister chromatids
d. spindle formation
e. separation of the spindle poles
6. A human cell containing 22 autosomes and a Y chromosome in
a. a sperm
b. an egg
c. a zygote
d. a somatic cell of a male
e. a somatic cell of a female
7. Homologous chromosomes move toward opposite poles of a dividing cell during
a. mitosis
b. meiosis I
c. meiosis II
d. fertilization
e. binary fission
8. Meiosis II is similar to mitosis in that
a. sister chromatids separate during anaphase
b. DNA replicates before the division
c. the daughter cells are diploid
d. homologous chromosomes synapse
e. the chromosome number is reduced
9. If the DNA content of a diploid cell in the G1 phase of the cell cycle is x, then the DNA content of the
same cell at metaphase of meiosis I would be
a. 0.25x
b. 0.5x
c. x
d. 2x
e. 4x
10. If we continued to follow the cell lineage from question 5, then the DNA content of a single cell at
metaphase of meiosis II would be
a. 0.25x
b. 0.5x
c. x
d. 2x
e. 4x
11. A black guinea pig crossed with an albino guinea pig produces 12 black offspring. When the albino
is crossed with a second black one, 7 blacks and 5 albinos are obtained. What is the best explanation for
this genetic situation? Write genotypes for the parents, gametes, and offspring.
12. A man with type A blood marries a woman with type B blood. Their child has type O blood. What
are the genotypes of the parents?
a. IAIA x IBIB
b. IAi x IBIB
c. IAi x IBi
d. ii x ii
13. A man has six fingers on each hand and six toes on each foot. His wife and their daughter have the
normal number of digits. Extra digits is a dominant trait. What fraction of this couple’s children would
be expected to have extra digits?
a. 0%
b. 25%
c. 50%
d. 75%
14. A person mates a red flower with a white flower. The F1 generation has all pink flowers. The F2
generation exhibits red, pink, and white flowers. What is the most logical pattern of inheritance for this
trait?
a. Complete dominance
b. Incomplete dominance
c. Codominance
d. Blending
15. Which of the following are Mendel’s laws?
a. Law of Independent Assortment
b. Law of Segregation
c. Law of Chromosomal Inheritance
d. A and B
E. All of the above
16. A man with hemophilia (a recessive, sex-linked condition) has a daughter of normal phenotype. She
marries a man who is normal for the trait. What is the probability that a daughter of this mating will be a
hemophiliac? That a son will be hemophiliac?
17. Pseudohypertrophic muscular dystrophy is an inherited disorder that causes gradual deterioration of
the muscles. It is seen almost exclusively in boys born to apparently normal parents and usually results
in death in the early teens. What are the characteristics of inheritance in this disorder?
a. Dominant; sex-linked
b. Dominant; autosomal
c. Recessive; sex-linked
d. Recessive; autosomal
18. Women born with an extra X chromosome (XXX) are healthy and phenotypically indistinguishable
from normal XX women. What is the likely explanation for this finding?
a. Inactivation of the autosomal chromosomes
b. Inactivation of the X chromosome
c. The X chromosome contains very few genes
d. None of the above
19. Assume that genes A and B are linked and are 50 map units apart. An animal heterozygous at both
loci is crossed with one that is homozygous recessive at both loci. What percentage of the offspring will
show phenotypes resulting from crossovers? If you did not know that genes A and B were linked, how
would you interpret the results of this cross?
20. Banana plants, which are triploid, are seedless and therefore sterile. Propose a possible explanation.
Vocabulary
Homozygous
Heterozygous
Dominant
Recessive
Gene
Chromosome
Trait
Genotype
Phenotype
Linked genes
Independent assortment
Dependent assortment
Sex-linked trait
Autosomal trait
Allele
Monohybrid cross
Dihybrid cross
Crossing over
Homologous chromosomes
Sister chromatids
Gamete
Locus
Recombinant
Sex chromosome
Hemizygous
Synapsis