Download Part I: Multiple Choice ______1. A haploid cell is a cell a. in which

Part I: Multiple Choice
______1. A haploid cell is a cell
a. in which the genes are arranged haphazardly.
b. containing only one copy of each chromosome.
c. that has resulted from the process of mitosis.
d. with twice the number of chromosomes of a diploid cell.
______2. The members of a homologous pair of chromosomes
a. are identical in size and appearance.
b. contain identical genetic information.
c. separate to opposite poles of the cell during mitosis.
d. are found only in haploid cells.
______3. For a prokaryote cell to divide, which of the following must occur?
a. DNA replication, segregation of DNA, and cytokinesis
b. DNA replication, crossing over, and segregation of DNA
c. DNA replication and segregation of DNA
d. A reproductive signal, DNA replication, segregation, and cytokinesis
______4. Bacteria typically have _______, whereas eukaryotes have _______.
a. one chromosome that is usually circular; many chromosomes that are linear
b. several chromosomes that are circular; many chromosomes that are linear
c. one chromosome that is linear; many chromosomes that are circular
d. two chromosomes that are usually circular; eight chromosomes that are linear
______5. The products of mitosis are
a. one nucleus containing twice as much DNA as the parent nucleus.
b. two genetically identical cells.
c. four nuclei containing half as much DNA as the parent nucleus.
d. four genetically identical nuclei.
______6. . A typical eukaryotic cell cycle consists of
a. mitosis and meiosis.
b. G1, the S phase, and G2.
c. prophase, metaphase, anaphase, and telophase.
d. interphase, mitosis, and cytokinesis.
7.–12. Match the eukaryotic cell cycle phase in the list below with the descriptions that follow. Each
phase may be used once, more than once, or not at all.
a. G1
b. S phase
c. G2
d. M phase
e. Interphase
______7. Cytokinesis occurs
______8. Replication of DNA
______9. Includes the G1 and G2 phases
______10. Segregation of DNA
______11. Cell grows and prepares to replicate the DNA
______12. Results in a human cell containing 92 chromatids
______13. A bacterial cell gives rise to two genetically identical daughter cells by a process known as
a. mitosis.
b. meiosis.
c. binary fission.
d. fertilization.
______14. Cells in the intestinal epithelium divide continuously so that cells lost from the surface of
the intestinal lining are replaced. A microscopic examination of the live cells would show that most of
them
a. are in mitosis.
b. are in interphase.
c. have condensed chromatin (chromosomes).
d. Both a and c
______15. During mitosis and meiosis the chromatin condenses. Which of the following processes
takes place more easily because of this compaction?
a. The orderly distribution of genetic material to two new nuclei
b. The replication of the DNA
c. Exposing the genetic information on the DNA
d. The disappearance of the nuclear membrane
______16. In plant cells, cytokinesis is accomplished by the formation of a(n)
a. aster.
b. membrane furrow.
c. equatorial plate.
d. cell plate.
______17. The initiation of the S phase of the cell cycle depends on a pair of molecules called
_______ and _______.
a. actin; myosin
b. Cdk’s; cyclin
c. ligand; receptor
d. insulin; glucagon
______18. In an organism with a diploid number of 8, a gamete has _______ chromosomes, a liver
cell has _______ chromosomes, and a cell undergoing meiosis at meiotic metaphase I has _______
chromosomes.
a. 8; 8; 8
b. 4; 4; 8
c. 8; 4; 4
d. 4; 8; 8
______19. Which of the following statements about sister chromatids is false?
a. They arise by replication during S phase.
b. They separate from each other during each mitotic anaphase.
c. They usually contain identical versions of the same genetic information.
d. They separate from each other during meiosis I.
______20. During meiosis I in humans, one of the daughter cells receives
a. only maternal chromosomes.
b. a mixture of maternal and paternal chromosomes.
c. the same number of chromosomes as that of a diploid cell.
d. a sister chromatid from each chromosome.
______21. One difference between mitosis and meiosis I is that
a. homologous chromosome pairs form tetrads during mitosis.
b. chromosomes do not replicate in the interphase preceding meiosis.
c. homologous chromosome pairs form tetrads during meiosis but not during mitosis.
d. sister chromatids separate during meiosis but not during mitosis.
______22. The exchange of genetic material between chromatids on homologous chromosomes
occurs during
a. interphase.
b. mitosis and meiosis.
c. prophase I.
d. anaphase I.
______23. The difference between asexual and sexual reproduction is that
a. asexual reproduction occurs only in bacteria, whereas sexual reproduction occurs in plants and
animals.
b. asexual reproduction results from meiosis, whereas sexual reproduction results from mitosis.
c. asexual reproduction results in an organism that is identical to the parent, whereas sexual
reproduction results in an organism that is not identical to either parent.
d. asexual reproduction results from the fusion of two gametes, whereas sexual reproduction produces
clones of the parent organism.
______24. Which of the following statements about mitosis is true?
a. The chromosome number in the resulting cells is halved.
b. DNA replication is completed in prophase.
c. Crossing over occurs during prophase.
d. Two genetically identical daughter cells are formed.
______25. A diploid human cell normally has 23 pairs of homologous chromosomes, but as a
woman ages, the chances of nondisjunction increase. Imagine that a gamete is produced in which the
two homologues of chromosome 21 have failed to separate. If one of the produced gametes are
fertilized with a normal sperm, the embryo’s cells will contain _______ chromosomes.
a. 23
b. 24
c. 46
d. 45
______26. The fact that most monosomies and trisomies are lethal to human embryos illustrates the
a. importance of the orderly distribution of genetic material during meiosis.
b. exchange of genetic information during crossing over.
c. advantage of sexual reproduction to the survival of a population.
d. formation of haploid gametes as a result of meiosis.
______27. Different forms of a gene are called
a. traits.
b. phenotypes.
c. genotypes.
d. alleles.
______28. A pea plant with red flowers is test crossed, and one-half of the resulting progeny have
red flowers, while the other half has white flowers. Therefore, the genotype of the test-crossed parent
was
a. RR.
b. Rr.
c. rr.
d. either RR or Rr.
______29. The genotype of an organism that expresses a dominant trait can be determined by
a. crossing the organism with a homozygous dominant organism.
b. crossing the organism with a heterozygous dominant organism.
c. crossing the organism with a homozygous recessive organism.
d. observing the genotype of the progeny from any cross.
______30. Classical albinism results from a recessive allele. Which of the following is the expected
ratio for the progeny when a normally pigmented male with an albino father has children with an
albino woman?
a. 3/4 normal, 1/4 albino
b. 3/4 albino, 1/4 normal
c. 1/2 normal,1/2 albino
d. All normal
______31. Which of the following statements about a dihybrid cross is true?
a. It results in a genotypic ratio of 2:1.
b. It results in offspring of lower quality than that of the parents.
c. It results in two different phenotypes in the F2 generation.
d. It is a cross between identical double heterozygotes.
______32. Mendel’s dihybrid crosses
a. resulted in four different phenotypes.
b. led to the formation of the law of independent assortment.
c. involved unlinked genes.
d. All of the above
______33. In cocker spaniels, black color (B) is dominant over red (b), and solid color (S) is
dominant over spotted (s). If the genes are unlinked, and the offspring of BBss and bbss individuals
are mated with each other, and then two of the F1 generation are mated with each other, what fraction
of the next generation (F2) will be black and spotted?
a. 9/16
b. 3/4
c. 3/16
d. 1/16
______34. Separation of the alleles of a single gene into different gametes is called
a. segregation.
b. independent assortment.
c. heterozygous separation.
d. recombination.
______35. The particular allele of a gene that is present in most individuals in nature is referred to
as
a. dominant.
b. recessive.
c. epistatic.
d. wild type.
______36. Which of the following statements about Mendelian genetics is false?
a. Alternative forms of genes are called alleles.
b. In any population, only two alleles can exist for a given gene.
c. A genotype is a description of an individual’s alleles.
d. Individuals with the same phenotype can have different genotypes.
______37. In a species of wild lupine flower, the smooth seed allele (S) is completely dominant over
the wrinkled seed allele (s). If the alleles for height are incompletely dominant, such that TT is tall, Tt
is intermediate, and tt is short, what will result from crossing a smooth-seeded, short (SStt) plant with
a wrinkled-seeded, tall (ssTT) plant?
a. One-half will be smooth-seeded and intermediate height; one-half will be smooth-seeded and tall.
b. All the progeny will be smooth-seeded and tall.
c. All the progeny will be smooth-seeded and short.
d. All the progeny will be smooth-seeded and intermediate in height.
______38. In Netherlands dwarf rabbits, a gene showing intermediate inheritance produces three
phenotypes. Rabbits that are homozygous for one allele are small; individuals that are homozygous
for the other allele are deformed and die; heterozygous individuals are dwarf. If two dwarf rabbits are
mated, what proportion of their surviving offspring should be dwarf?
a. 1/4
b. 1/3
c. 1/2
d. 2/3
______39. Despite the law of independent assortment, when two loci are on the same chromosome,
the phenotypes of the progeny sometimes do not fit the predicted phenotypes. This outcome can be
explained by the phenomenon of
a. linkage
b. inversions.
c. chromatid affinities.
d. segregation
______40. Very few genes have been located on the Y chromosomes. Y-linked genes include a gene
called SRY. A male with this gene will
a. usually pass it to his sons, but occasionally also to a daughter.
b. only pass the gene to his sons.
c. only pass the gene to his daughters.
d. only pass the gene to his grandsons.
______41. In humans, spotted teeth are caused by a dominant sex-linked gene. A man with spotted
teeth whose father had normal teeth marries a woman with normal teeth. Therefore,
a. all of their daughters will have normal teeth.
b. all of their daughters will have spotted teeth.
c. all of their children will have spotted teeth.
d. half of their sons will have spotted teeth.
42.–43. Cleft chin is an X-linked recessive trait. Assume that a man with a cleft chin marries a
woman that is heterozygous.
______42. What percent of their female progeny will show the cleft chin trait?
a. 0 percent
b. 25 percent
c. 50 percent
d. 100 percent
______43. What percent of their male progeny will show the cleft chin trait?
a. 0 percent
b. 25 percent
c. 50 percent
d. 100 percent
______44. After mapping a chromosome, a scientist finds that genes Q and R are twenty units apart,
and genes R and S are eleven units apart, and genes Q and S are thirty units apart. The sequence on
the chromosome would be
a. RSQ
b. SQR
c. QRS
d. RQS
______45. Match the following disorders with the correct pedigree:
Sickle cell anemia (recessive, autosomal)
Lou Gehrig’s disease (dominant, autosomal)
Hemophilia (X-linked)
a. A – Sickle cell; C – Lou Gehrig’s disease; D – hemophilia
b. B – Sickle cell; D – Lou Gehrig’s disease; A – hemophilia
c. C – Sickle cell; D – Lou Gehrig’s disease; B – hemophilia
d. B – Sickle cell; C – Lou Gehrig’s disease; A – hemophilia
______46. Imagine that there is a mutation in the cyclin gene such that its gene product is
nonfunctional. What kind of effect would this mutation have on a skin cell in the area of a cut?
a. Cdk would not be synthesized.
b. There would be no effect, because skin cells do not replicate.
c. The cell would not be able to enter G1.
d. The cell would be unable to reproduce itself.
______47. The 9:3:3:1 ratio is obtained
a. through a dihybrid cross in which the genes are linked on the same chromosome.
b. through a dihybrid cross in which the genes are on different chromosomes.
c. when crossing over occurs.
d. in a test cross.
______48. A woman of blood group A has a child with a man of blood group B. The child’s blood is
type O. What are the genotypes of the parents?
a. Mother: IAIA; father: IBIa
b. Mother: IAIO; father: IBIb
c. Mother: IAIO; father: IBIO
d. Mother: IAIB; father: IBIO
______49. Which statement about linkage of genes is false?
a. Genes on the same chromosome are said to be linked.
b. Genes on the same chromosome assort independently.
c. Crossing over results in recombinant phenotypes.
d. Genes on the same chromosome that are far apart have a higher recombination frequency than
those that are close together.
______50. Which statement about crossing over is false?
a. Crossing over explains why some genes on the same chromosome are not always inherited together.
b. Crossing over occurs during mitosis.
c. Crossing over results in recombinant chromatids.
d. Recombination frequencies may be used to map the order of genes on a chromosome.
Short Answer:
1. There are three major regulatory checkpoints in the cell cycle: G1/S, G2/M, and Spindle Checkpoint
(Metaphase Checkpoint). What is being “checked” at each of these checkpoints?
G1/S:
G2/M:
Spindle (Metaphase):
2. In a certain species of flowering plant, the purple allele, P is dominant to the yellow allele p.
A student performed a cross between a purple-flowered plant and a yellow-flowered plant. When planted, the
180 seeds that were produced from the cross matured into 105 plants with purple flowers and 75 plants with
yellow flowers.
a. Calculate the chi-squared value for the null hypothesis that the purple-flowered parent was heterozygous for
the flower-color gene. Give your answer to the nearest tenth.
b. Using p = 0.05, should you accept or reject your hypothesis? __________
c. What does this mean?
3. In tomatoes, tall is dominant to short and smooth fruits are dominant to hairy fruits. A plant that is
homozygous for both dominant traits is crossed with a plant that is homozygous for both recessive traits. The F 1
progeny are tested and crossed with the following results: 78 tall, smooth fruits; 82 short, hairy fruits; 22 tall,
hairy fruits; and 18 short, smooth fruits.
a. Are these genes linked? _________
b. What is the recombination frequency? ( Show your work )
c. How many map units apart are these genes from each other?
4. Fruit flies (Drosophila melanogaster) with a wild-type phenotype have gray bodies and red eyes. Certain
mutations can cause changes to these traits. Mutant flies may have a black body and/or cinnabar eyes. To study
the genetics of these traits, a researcher crossed a true- breeding wild-type male fly (with gray body and red
eyes) with a true-breeding female fly with a black body and cinnabar eyes. All of the F1 progeny displayed a
wild-type phenotype. Female flies from the F1 generation were crossed with true-breeding male flies with black
bodies and cinnabar eyes. The table represents the predicted outcome and the data obtained from the cross.
Explain the difference between the expected data and the actual numbers observed.
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Reference Sheet:
o = observed individuals with observed genotype
e = expected individuals with observed genotype
Degrees of Freedom equals the number of distinct possible
outcomes minus one.
Chi-Square Table:
Degrees of Freedom
p
1
2
3
4
5
6
7
8
0.05
3.84
2.99
7.82
9.49
11.07
12.59
14.07
15.51
0.01
6.64
9.32
11.34
13.28
15.09
16.81
18.48
20.09
Probability Rules:
Name_____________________
Miss Badean
Date__________
AP Biology
Test #3: The Cell Cycle, Regulation
of the Cell Cycle, and Mendelian
Genetics
Score __________