Bio 178 (Principles of Biology) Spring 2006: Practice Questions for Exam 4
Do the Practice Exam under exam conditions. This exam is longer than the real thing will be, but if you are comfortable
with all the questions here you should be fine with the exam. Also, see the study guide for requirements and use your
quizzes to study.
MULTIPLE CHOICE:
1.
Gametes:
(A) are haploid cells.
(B) fuse to form a zygote.
(C) are produced by meiosis.
(D) all of the above.
(E) none of the above.
2.
In prophase I of meiosis:
(A) crossing over occurs.
(B) chromosomes reach opposite poles of the cell.
(C) chromosomes align at the cell equator.
(D) the nuclear envelope is reformed.
(E) sister chromatids separate.
3.
In anaphase I of meiosis:
(A) crossing over occurs.
(B) the cytoplasm divides.
(C) the homologues separate.
(D) sister chromatids separate.
(E) the centrioles form the spindle fibers.
4.
Alternation of generations refers to:
(A) the alternation of egg and sperm.
(B) the alternation of a haploid and a diploid generation.
(C) the presence of 2 sexes.
(D) the dependence of one generation on the next.
(E) none of the above.
5.
Genetic variation is ensured by:
(A) random fertilization.
(B) crossing over during meiosis.
(C) independent assortment.
(D) all of the above.
(E) none of the above.
6.
Trisomy is:
(A) one chromosome too few.
(B) tetraploidy.
(C) a type of cancer.
(D) a tumor suppressor gene.
(E) one chromosome too many.
7.
The pairing of homologues in prophase I of meiosis is called:
(A) crossing over.
(B) synapsis.
(C) gametogenesis.
(D) independent assortment.
(E) kinetochore.
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8.
Ploidy is:
(A) breakdown of the nucleus in cell division.
(B) an attachment between homologues that have crossed over.
(C) detachment of the chromosomes from the kinetochore microtubules at the end of mitosis.
(D) the number of sets of chromosomes possessed by a cell.
(E) none of the above.
9.
Mitosis and meiosis differ in:
(A) the number of cell divisions that occurs.
(B) the final ploidy of the daughter cells.
(C) the number of daughter cells produced.
(D) the composition of the spindle fibers.
(E) A, B, and C.
10.
To ensure true-breeding parental plants Mendel:
(A) self fertilized each variety for several generations.
(B) crossed 2 varieties with alternate traits.
(C) self-fertilized the F1 generation.
(D) A and B.
(E) none of the above.
11.
When Mendel crossed 2 varieties of true-breeding plants the F1 generation were:
(A) 100% heterozygous.
(B) 100% homozygous.
(C) 50% heterozygous.
(D) 75% heterozygous.
(E) none of the above.
12.
The degree of earlobe attachment in humans is inherited as a simple dominant of free earlobes, or as a recessive allele of
attached earlobes. What is the probability that a woman with attached earlobes will have children with attached earlobes
if their father has free earlobes, but his father had attached earlobes?
(A) 1 in 2.
(B) 3 in 4.
(C) 100%.
(D) 1 in 10.
(E) none.
13.
Alleles are:
(A) homologous chromosomes.
(B) alternate forms of a gene.
(C) the appearance of an individual.
(D) the genotype of an individual.
(E) heterozygous individuals.
The following statement is for questions 14 and 15:
In a particular breed of cats, black (B) is dominant to white (b). A black heterozygous cat is crossed with a black homozygous cat.
14.
The genotypic ratio is:
(A) 1:1 homozygous to heterozygous.
(B) 3:1 heterozygous to homozygous.
(C) All heterozygous.
(D) All black.
(E) 1:1 black to white.
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15.
The phenotypic ratio is:
(A) 1:1 homozygous to heterozygous.
(B) 3:1 heterozygous to homozygous.
(C) All heterozygous.
(D) All black.
(E) 1:1 black to white.
16.
In lab, you cross a blue-flowered plant variety with a yellow-flowered variety. You obtain 50% blue plants in the F 1
generation. The blue-flowered plants were probably:
(A) homozygous dominant.
(B) homozygous recessive.
(C) heterozygous.
(D) sterile.
(E) it is impossible to confirm the parental genotype from the information given.
17.
You could confirm the genotypes in the above question by:
(A) performing a test-cross.
(B) self-fertilizing the F1 generation.
(C) crossing with a homozygous recessive plant.
(D) crossing with a homozygous dominant plant.
(E) A and C.
18.
Which of the following represents an individual that is homozygous for a recessive trait?
(A) AA.
(B) aa.
(C) Aa.
(D) AA and Aa.
(E) none of the above.
19.
The organization of the chromosomes of an individual can be shown by a(n):
(A) aneuploid.
(B) ultrasound.
(C) pleiotrope.
(D) purine.
(E) karyotype.
The following statement is for questions 20 to 22.
Two common coat colors for Shetland sheepdogs are sable and tricolor. Sable dogs (BB) are blonde and tricolored dogs (bb) are
black with a white collar and tan eyebrows. A dog that is heterozygous for coat color (Bb) is called a tri-factored sable and is
darker than a dog that is homozygous for sable (BB).
20.
A sable dog is crossed with a tricolored dog. What are the possible colors of the progeny?
(A) All tri-factored sable.
(B) All sable.
(C) All blonde.
(D) Both sable and tricolored.
(E) both tricolored and tri-factored.
21.
One of the progeny from question 20 is crossed with a tricolored dog. What coat colors are possible?
(A) All tri-factored sable.
(B) All sable.
(C) All blonde.
(D) Both sable and tricolored.
(E) both tricolored and tri-factored.
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22.
A tri-factored sheltie has a litter of puppies. Two of the pups are tri-factored and 2 of the pups are sable. What color was
the father of the puppies?
(A) sable.
(B) tricolored.
(C) tri-factored.
(D) either A or B.
(E) either A or C.
23.
A cross between 2 individuals results in a 9:3:3:1 ratio of phenotypes. This is a ___________ cross.
(A) monohybrid
(B) dihybrid
(C) testcross
(D) punnett square
(E) none of the above
24.
Mendel’s second law is also known as:
(A) the law of segregation.
(B) the law of independent assortment.
(C) the first law of thermodynamics.
(D) meiosis.
(E) increasing entropy.
25.
The law of segregation refers to:
(A) separation of gametes.
(B) separation of homologous chromosomes in anaphase I.
(C) separation of homologous chromosomes in metaphase I.
(D) independent assortment in metaphase I.
(E) independent assortment in metaphase II.
26.
A Rh-negative mother pregnant with her second Rh-positive child may cause the red blood cells of the fetus to clump.
This is because the mother has:
(A) anti-A antibodies
(B) anti-B antibodies
(C) anti-Rh antibodies
(D) an allergic response to pregnancy
(E) HIV
27.
A woman with blood type A has a child with a man that is blood type B. What are the possible genotypes of the child?
(A) A.
(B) B.
(C) AB.
(D) O.
(E) all of the above.
28.
In snapdragons, pink-flowered plants are produced when red-flowered plants are crossed with white-flowered plants. This
type of inheritance can be described as:
(A) a completely dominant trait.
(B) simple dominant and recessive traits.
(C) pleiotropy.
(D) incomplete dominance.
(E) polygeny.
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29.
During interphase, chromosomes:
(A) line up at the cell equator.
(B) separate into sister chromatids.
(C) coil tightly around histones.
(D) replicate.
(E) A and C.
30.
At the G1 checkpoint:
(A) cytokinesis starts.
(B) sister chromatids separate and move to opposite poles of the cell.
(C) the decision is made to divide, delay, or enter a resting stage.
(D) cancerous cells begin cell division.
(E) all of the above.
31.
The cell cycle of eukaryotes is controlled:
(A) at 3 checkpoints.
(B) during S phase.
(C) during C phase.
(D) during metaphase and telophase.
(E) none of the above.
32.
In metaphase of mitosis:
(A) the homologues align at the cell equator.
(B) the homolgues separate.
(C) chromosomes align at the cell equator.
(D) the nuclear envelope breaks down.
(E) the chromosomes condense.
33.
The structure of chromosomes in all stages of the cell cycle is partly maintained by:
(A) covalent bonding between the strands of the double helix.
(B) ionic bonding between the strands of the double helix.
(C) the centromere.
(D) winding of the DNA molecule around a core of proteins.
(E) the spindle fibers.
34.
Sister chromatids are:
(A) only seen in prokaryotes.
(B) homologous chromosomes.
(C) formed only in meiosis.
(D) pairs of centrioles.
(E) duplicated DNA held together by a centromere.
35.
Human nerve cells are:
(A) somatic cells.
(B) produced by binary fission.
(C) constantly reproducing.
(D) diploid.
(E) A and D.
36.
In S phase of mitosis the _____ is synthesized.
(A) cell wall
(B) plasma membrane
(C) Golgi complex
(D) DNA
(E) RNA
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37.
___________ are responsible for the formation of a cleavage furrow in mitosis and meiosis.
(A) Microtubules
(B) Actin filaments
(C) Intermediate filaments
(D) Spindle fibers
(E) Tubulin subunits
38.
The prokaryotic cell cycle consists of:
(A) interphase with 3 checkpoints.
(B) DNA replication.
(C) binary fission.
(D) B and C.
(E) all of the above.
39.
Mitosis can be defined as:
(A) nuclear division in somatic cells.
(B) nuclear division in germ cells.
(C) binary fission.
(D) cytoplasmic division in somatic cells.
(E) DNA replication.
40.
A cell plate is formed in:
(A) binary fission of prokaryotic cells.
(B) cytokinesis in animal cells.
(C) cytokinesis in plant cells.
(D) metaphase of mitosis.
(E) B and C.
41.
Spermatogenesis occurs in the:
(A) epididymis.
(B) seminiferous tubules.
(C) fallopian tubes.
(D) penis.
(E) A, B, and D.
42.
Which of the following is a diploid cell that has not begun the process of meiosis?
(A) Ovum
(B) Primary oocyte
(C) Spermatogonium
(D) Secondary spermatocyte
(E) B and C
43.
Where in the body is an ovum fertilized?
(A) Ovary
(B) Fallopian tube
(C) Uterus
(D) Body cavity
(E) A, B, and C
44.
Which of the following secretes the hormone hCG?
(A) Testis
(B) Follicle
(C) Ovary
(D) Corpus luteum
(E) Embryo
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45.
What is the function of the acrosome?
(A) Release of enzymes that penetrate the protective layers of the egg.
(B) Provide energy for flagellar movement.
(C) Anchor flagellum.
(D) Hormone secretion.
(E) Assist spermatids in maturation.
The following statement is for question 46 and 47. Red-green colorblindness is a sex-linked trait. A woman with normal color
vision whose father was colorblind has children with a colorblind man.
46.
What is the probability that one of their children will be a colorblind female?
(A) 25%.
(B) 50%.
(C) 75%.
(D) 100%.
(E) 0.
47.
What is the probability that a son will have normal color vision?
(A) 25%.
(B) 50%.
(C) 75%.
(D) 100%.
(E) 0.
48.
Autosomes are:
(A) homologous chromosomes that have failed to separate in meiosis.
(B) chromosomes that are not involved in sex determination.
(C) sex chromosomes.
(D) sex-linked genes.
(E) recessively inherited disorders.
49.
The sex of a child is determined by:
(A) the female gamete.
(B) the male gamete.
(C) sex chromosomes.
(D) temperature.
(E) B and C.
50.
Which of the following is not true of sickle cell anemia?
(A) It is inherited as a recessive condition.
(B) Heterozygotes have the disease.
(C) It is caused by a polar amino acid being replaced by a non-polar amino acid.
(D) It is particularly prevalent amongst blacks.
(E) None of the above – they are all true.
51.
The type of hemophilia that occurs in the descendents of Queen Victoria:
(A) is sex-linked.
(B) is carried on the Y chromosome.
(C) causes the red blood cells to sickle.
(D) causes the red blood cells to clump.
(E) all of the above.
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52.
Amniocentesis:
(A) allows prenatal diagnosis of many genetic disorders.
(B) allows a fetus to be imaged.
(C) is a procedure involved in genetic engineering.
(D) is a term for the granting amnesty to prisoners of war.
(E) none of the above.
53.
The allele for Huntington’s disease persists because:
(A) it is recessive.
(B) it increases resistance to malaria.
(C) symptoms of the disease do not become evident until middle age.
(D) females are only carriers, they do not have the disease.
(E) A and B.
54.
Humans with an abnormal chromosome number are said to be:
(A) monosomic.
(B) trisomic.
(C) haploid.
(D) aneuploid.
(E) asexual.
55.
A person with Klinefelter syndrome is a:
(A) sterile female, short in stature, with a webbed neck.
(B) tall, sometimes sterile, but otherwise normal female.
(C) sterile male with female characteristics.
(D) dead male.
(E) a male that is fertile but has an extra Y chromosome.
56.
The genotype of a person with Turner syndrome is:
(A) OY.
(B) OX.
(C) XXX.
(D) XXY.
(E) XYY.
57.
In 1910, after studying eye color in Drosophila, Morgan and colleagues realized that:
(A) the trait was sex linked.
(B) the white-eyed trait segregated with the X chromosome.
(C) the white eyed trait segregated with the Y chromosome.
(D) A and B.
(E) A and C.
58.
The SRY gene is carried on chromosome __________ and functions in __________.
(A) 21, eye color
(B) X, eye color
(C) Y, eye color
(D) X, sex determination
(E) Y, sex determination
59.
Barr bodies:
(A) have fewer genes than non-condensed X chromosomes.
(B) are Y chromosomes.
(C) are inactivated X chromosomes.
(D) are found on the rough endoplasmic reticulum.
(E) are “junk” DNA ejected from the oocyte after meiotic division.
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SHORT ANSWER QUESTIONS:
60. A brown female mouse (Jane) is crossed with 2 black male mice (John and Bob). In the progeny of Jane and Bob 8 mice are
black and 9 mice are brown, and in the progeny of Jane and John all 15 mice are black. What are the genotypes of the parents?
61. When Mendel used pollen from a dwarf strain of peas to fertilize the flowers of a true-breeding tall line, and planted the
resulting seeds, only tall plants grew from them. When he crossed these hybrids to the dwarf plants he observed among the
offspring 87 tall and 79 dwarf plants. Diagram the cross.
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62. The diagram shows a cell that has 6 chromosomes and is in prophase of mitosis. Draw the cell in all the stages of mitosis and
meiosis. Make sure you label your diagrams. (In the exam you will be given a subset of the stages, so don’t worry if this takes
longer than the allotted time). Practice drawing these from memory – you will have to do it in the exam.
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63. In watermelons, the genes for green color and short shape are dominant over their alleles for striped color and long shape.
(a) Suppose a plant with long-striped fruit is crossed with a plant heterozygous for both these characters. What phenotypes would
be produced and in what ratios?
(b) Repeat part (a) using a cross between 2 watermelons that are heterozygous for both characters.
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64. If the litter resulting from the mating of 2 short-tailed cats contains 3 kittens without tails, 2 with long tails, and 6 with short
tails, what would be the simplest way of explaining the inheritance of tail length in these cats? (SHOW ALL THE GENOTYPES
AND PHENOTYPES OF PARENTS AND PROGENY AND EXPLAIN WHAT TYPE OF INHERITANCE THIS IS).
65. Coat color in rabbits is determined by multiple alleles. The alleles in this series are C + (full color), Cch (chinchilla), and Ch
(Himalayan). Dominance is from left to right as shown C +> Cch > Ch . In a cross of C+ Cch X Cch Ch what proportion of the
progeny will be Himalayan? (Show working)
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66. An individual lost his father to Huntington’s disease. His mother is healthy and in her 60’s. Show all working below.
(a) What is the probability that the individual will develop Huntington’s disease?
(b) What is the probability that his children will be carriers of the disease?
67. A form of hemophilia is determined by a gene on the X chromosome in humans. Assume that a phenotypically normal woman
whose father had hemophilia is married to a normal man. What is the probability that their first daughter will have hemophilia?
Draw a pedigree (showing all 3 generations) and explain your answer.
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68. The following pedigree is concerned with an inherited dental abnormality, amelogenesis imperfecta. Normal individuals and
carriers are represented by the white symbols.
(a) What mode of inheritance best accounts for the transmission of this trait?
(b) Write all the genotypes of the family members (that are possible to deduce) on the pedigree.
69. For each of the pedigrees below, deduce the inheritance of the condition. Then, for each pedigree label all the individuals (that
are possible to deduce) with their genotype.
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70. Male house cats are either black or orange; females are black, orange, or calico.
(a) If these coat-color phenotypes are governed by a sex-linked gene, how can these observations be explained?
(b) What phenotypic and genotypic ratios would be expected for the F 1 of a cross between an orange female and a black male.
(c) Repeat part (b) for the reciprocal of the cross described there.
(d) Half of the females produced by a certain kind of mating are calico, and half are black. Half of the males are orange and half
are black. What colors are the parents in this kind of mating?
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