Chapter 8
It has been proposed that miscarriages due to genetic defects occur in _____ of all pregnancies. A) 1/10 B) 1/8 C) ¼ D) ½
1/8
For a species with four pairs of chromosomes, ________ chromosome combinations are possible. A) 4 B) 8 C) 16 D) 20
16
Immediately following mitosis, a group of cells is found to have an average of 8 picograms of DNA per nucleus. How many picograms of DNA would be found in a nucleus during prophase of the next mitosis? A) 4 B) 8 C) 16 D) 2
16
In a diploid cell with 5 chromosome pairs (2n = 10), how many sister chromatids will be present during prophase of mitosis? A) 5 B) 10 C) 20 D) 40
20
How many chromosomes does an individual with Turner syndrome have? A) 2n + 1 B) n + 1 C) 2n − 1 D) n - 1
2n − 1
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 will be A) 0.25x. B) 0.5x. C) x. D) 2x.
2x
Starting with a fertilized egg (zygote), a series of six cell divisions would result in how many cells? A) 12 B) 16 C) 32 D) 64
32
What chromosomes belong to a normal human female? A) 22 autosomes and 2 X chromosomes B) 44 autosomes and 2 X chromosomes C) 44 autosomes, one X chromosome, and one Y chromosome D) 46 autosomes and two X chromosomes
44 autosomes and 2 X chromosomes
What is the chromosome number found in humans cells after meiosis I is completed? A) 46 autosomes B) 43 autosomes and 2 sex chromosomes C) 22 autosomes and a sex chromosome D) 44 autosomes and 2 sex chromosomes
44 autosomes and 2 sex chromosomes
What chromosomes belong to a normal human male? A) 22 autosomes and two Y chromosomes B) 44 autosomes and two Y chromosomes C) 44 autosomes, one X chromosome, and one Y chromosome D) 46 autosomes, one X chromosome, and one Y chromosome
44 autosomes, one X chromosome, and one Y chromosome
Of the following human genetic disorders due to nondisjunction, which one generally has the most severe impact on the health of the individual? A) 47, trisomy 21 B) 47, XXY C) 47, XXX D) 45, XO
47, trisomy 21
What percentage of Amanda's gametes would likely have the normal number of chromosomes? A) zero B) 100 percent C) 50 percent D) 25 percent
50 percent
Which is a possible chromosomal makeup for one daughter nucleus at telophase of mitosis? A) A B) B C) C D) D E) E
B
What is the difference between a benign and a malignant tumor? A) Benign tumors are composed of cancer cells; malignant tumors are not. B) Benign tumors are not the result of a failure of a cell cycle control system; malignant tumors are. C) Benign tumors do not metastasize; malignant tumors do. D) Benign tumors do not form lumps; malignant tumors do form lumps.
Benign tumors do not metastasize; malignant tumors do.
Which of the following occurs during interphase? A) Chromatin becomes tightly coiled. B) Chromosome duplication occurs. C) Sister chromatids separate. D) The mitotic spindle forms
Chromosome duplication occurs.
Which of the following processes occurs when homologous chromosomes cross over in meiosis I? A) Two sister chromatids get tangled, resulting in one re-sequencing its DNA. B) Two sister chromatids exchange identical pieces of DNA. C) Corresponding segments of non-sister chromatids are exchanged. D) Maternal alleles are "corrected" to be like paternal alleles and vice versa.
Corresponding segments of non-sister chromatids are exchanged.
Which of the following is a characteristic seen in prophase I that does NOT occur in prophase II? A) Chromosomes move to the middle of the cell. B) Spindle formation occurs. C) The number of chromosomes doubles. D) Crossing over occurs.
Crossing over occurs.
A major function of the mitotic spindle during M phase of the cell cycle is ________. A) cytokinesis B) condensation of chromosomes C) dissolving the nuclear membrane D) separation of sister chromatids
D) separation of sister chromatids
Examine the figure below. Nucleosomes are made of ________. A) RNA and protein B) DNA C) proteins D) DNA and histone proteins
DNA and histone proteins
Chromatin consists of ________. A) DNA and protein B) RNA and protein C) protein only D) DNA only
DNA and protein
Eukaryotic chromosomes are composed of ________. A) DNA and RNA B) DNA only C) DNA and proteins D) DNA and phospholipids
DNA and proteins
In meiosis, how does prophase I differ from prophase II? A) During prophase I there is one diploid cell; during prophase II there are two haploid cells. B) During prophase I chromosomes line up single file in the middle of the cell; during prophase II the chromosomes line up in double file in the middle of the cell. C) During prophase I the chromosomes coil up; the chromosomes are not coiled up during prophase II. D) In prophase I the sister chromatids are attached; in prophase II the sister chromatids are separated.
During prophase I there is one diploid cell; during prophase II there are two haploid cells.
Which of the following statements is true of a species that has a chromosome number of 2n = 16? A) The species is diploid with 32 chromosomes per cell. B) The species has 16 sets of chromosomes per cell. C) Each diploid cell has eight homologous pairs of chromosomes. D) A gamete from this species has four chromosomes.
Each diploid cell has eight homologous pairs of chromosomes.
The cell cycle normally halts within the ______ phase of interphase unless specific proteins of the cell cycle control system are present. A) G1 B) S C) G2 D) M phase
G1
Which of the following processes occur during meiosis but not mitosis? A) Haploid cells fuse to form diploid cells. B) Haploid cells multiply into more haploid cells. C) Diploid cells form haploid cells. D) A diploid cell combines with a haploid cell.
Haploid cells fuse to form diploid cells.
Which of the following is the best description of the events of anaphase I? A) Half of the chromosomes inherited from the mother go to one pole along with half of the chromosomes inherited from the father. B) Sister chromatids separate and the daughter chromosomes migrate to opposite poles. C) Homologous chromosomes randomly separate and migrate to opposite poles. D) All of the chromosomes inherited from the mother go to one pole of the cell, and all of the chromosomes inherited from the father go to the other pole.
Homologous chromosomes randomly separate and migrate to opposite poles.
If a cell has completed meiosis I and the first cytokinesis, and is just beginning meiosis II, which of the following is an appropriate description of its genetic contents? A) It has half the amount of DNA as the cell that began meiosis. B) It has half the chromosomes but twice the DNA of the parent cell. C) It has one-fourth the DNA and one-half the chromosomes as the parent cell. D) It is genetically identical to another cell formed from the same meiosis I event
It has half the amount of DNA as the cell that began meiosis.
Which statement accurately describes the structure of a eukaryotic chromosome? A) It is composed of a single strand of DNA. B) It is constructed as a series of nucleosomes wrapped around two double-stranded DNA molecules. C) Each chromosome can be a different size in different cell types of an organism. D) It is a single linear molecule of double-stranded DNA plus proteins.
It is composed of a single strand of DNA.
A(n) ________ is an example of an animal that can sometimes reproduce asexually by parthenogenesis. A) cat B) human C) Komodo dragon D) mouse
Komodo dragon
A couple has a child with Down syndrome. The mother is 39 years old at the time of delivery. What is the most probable cause of the child's condition? A) The woman inherited this tendency from her parents. B) The mother had a chromosomal duplication. C) One member of the couple underwent nondisjunction in somatic cell production. D) One of the gametes in the mother most likely underwent nondisjunction during meiosis.
One member of the couple underwent nondisjunction in somatic cell production.
How is plant cell cytokinesis different from animal cell cytokinesis? A) The cleavage furrow in plant cells is composed of carbohydrates; the cleavage furrow in animal cells is composed of microfilaments. B) Plant cells form a cell plate between the two daughter cells; animal cells form a cleavage furrow. C) The structural proteins of plant cells separate the two cells; in animal cells, a cell membrane separates the two daughter cells. D) Plant cells divide after metaphase but before anaphase; animal cells divide after anaphase.
Plant cells form a cell plate between the two daughter cells; animal cells form a cleavage furrow.
Chromosomes are copied during which phase of the cell cycle? A) M phase B) G1 C) S D) G2
S
How does natural selection apply to sexual reproduction as opposed to asexual reproduction? A) Sexual reproduction results in many new gene combinations, some of which will lead to differential reproduction. B) Sexual reproduction results in the greatest number of new mutations. C) Sexual reproduction allows the greatest number of offspring to be produced. D) Sexual reproduction utilizes far less energy than asexual reproduction.
Sexual reproduction results in many new gene combinations, some of which will lead to differential reproduction.
Which of these events occurs during anaphase? A) Sister chromatids become separate chromosomes. B) Chromosomes line up in the middle of the cell. C) The nuclear envelope reappears. D) The nuclear envelope breaks up.
Sister chromatids become separate chromosomes.
Which of the following statements describes a major difference between mitosis and meiosis I in a diploid organism? A) Sister chromatids separate in mitosis, while homologous pairs of chromosomes separate in meiosis I. B) Sister chromatids separate in mitosis, while homologous pairs of chromosomes separate in meiosis II. C) DNA replication takes place prior to mitosis, but not before meiosis I. D) Only meiosis I results in daughter cells that contain identical genetic information.
Sister chromatids separate in mitosis, while homologous pairs of chromosomes separate in meiosis I.
Which statement describes the chromosomal makeup of each daughter cell after telophase of meiosis I? A) The cells are diploid, and the chromosomes are each composed of a single chromatid. B) The cells are diploid, and the chromosomes are each composed of two chromatids. C) The cells are haploid, and the chromosomes are each composed of a single chromatid. D) The cells are haploid, and the chromosomes are each composed of two chromatids
The cells are haploid, and the chromosomes are each composed of two chromatids
How do cells at the completion of meiosis II compare with cells that are in prophase of meiosis I? A) The cells have half the number of chromosomes and half the amount of DNA. B) The cells have the same number of chromosomes and half the amount of DNA. C) The cells have half the number of chromosomes and one-fourth the amount of DNA. D) The cells have half the amount of cytoplasm and twice the amount of DNA.
The cells have half the number of chromosomes and one-fourth the amount of DNA.
Which statement is TRUE of a cell at the conclusion of meiosis I? A) The daughter cells no longer have pairs of homologous chromosomes. B) The chromosomes in the daughter cells are exact copies of the chromosomes in the parent cell prior to meiosis. C) Sister chromatids are separated. D) Four daughter cells are formed.
The daughter cells no longer have pairs of homologous chromosomes.
Which of the following occurs during prophase? A) Chromosomes line up on the midline of the cell. B) The nuclear envelope forms. C) Sister chromatids separate. D) The mitotic spindle begins to form
The mitotic spindle begins to form
Which of the following is an example of monosomy in humans? A) Down syndrome B) Klinefelter syndrome C) Turner syndrome D) trisomy X
Turner syndrome
________ is the only known condition in humans where having 45 chromosomes is not fatal. A) Turner syndrome B) Klinefelter syndrome C) Down syndrome D) trisomy X
Turner syndrome
With respect to her sex chromosomes, Amanda would be designated as ________. A) XYY B) XO C) XOY D) XX
XO
What is a syndrome? A) a characteristic facial appearance B) a genetic abnormality that leads to cancer at some stage in life C) a characteristic group of symptoms typically associated with a particular chromosomal aberration or gene mutation D) a single, specific symptom associated with a specific genetic disorder caused by nondisjunction
a characteristic group of symptoms typically associated with a particular chromosomal aberration or gene mutation
A cleavage furrow is ________. A) a ring of vesicles formed from the cell plate B) the separation of divided prokaryotes C) a groove in the plasma membrane between the two daughter nuclei D) the space that is created between two chromatids during anaphase
a groove in the plasma membrane between the two daughter nuclei
Which of these could lead to the mistake evident in the karyotype? A) a failure of cytokinesis after meiosis I in gamete formation B) a nondisjunction in meiosis II in gamete formation C) crossing over in meiosis I in gamete formation D) fertilization by two sperm in zygote formation
a nondisjunction in meiosis II in gamete formation
Through a microscope, you can see a cell plate beginning to develop across the middle of a cell and nuclei forming on either side of the cell plate. This cell is most likely ________. A) an animal cell in the process of cytokinesis B) an animal cell in anaphase of mitosis C) a plant cell in the process of cytokinesis D) a plant cell in metaphase of mitosis
a plant cell in the process of cytokinesis
For a species with a haploid number of 23 chromosomes, how many different combinations of maternal and paternal chromosomes are possible for the gametes? A) 23 B) 46 C) about 1,000 D) about 8 million
about 8 million
Sexual reproduction in humans ________. A) allows a haploid sperm cell to fertilize a haploid egg cell B) produces a haploid individual C) produces an individual with 23 chromosomes D) combines two diploid gametes, producing a zygote
allows a haploid sperm cell to fertilize a haploid egg cell
During which phase of mitosis do the chromatids become chromosomes? A) telophase B) anaphase C) prophase D) metaphase
anaphase
During which of the following phases of meiosis do homologous chromosomes separate? A) anaphase II B) prophase I C) metaphase II D) anaphase I
anaphase I
During which of the following phases of meiosis do centromeres split and sister chromatids migrate to opposite poles of the cell? A) anaphase I B) telophase I C) anaphase II D) telophase II
anaphase II
Homologous chromosomes ________. A) carry genes controlling the same inherited characteristics B) may be different lengths C) are a set of chromosomes that the cell received from one parent D) carry the same versions of all genes
are a set of chromosomes that the cell received from one parent
During cell division in eukaryotic cells, the nuclear envelope has to disappear to permit ________. A) DNA synthesis B) attachment of spindle microtubules to chromosomes C) separation of the centrosomes D) condensation of the chromosomes
attachment of spindle microtubules to chromosomes
Chromosomes that do NOT determine the sex of an individual are called ________. A) homologous chromosomes B) nonhomologous chromosomes C) sex chromosomes D) autosomes
autosomes
Many organisms spend most of their life cycle in the diploid state. If meiosis produces haploid cells, how is the diploid number restored for these types of organisms? A) by DNA replication B) through the transcription of DNA to RNA C) by synapsis of the homologous pairs of chromosomes during prophase of meiosis I D) by fertilization
by fertilization
Sexual reproduction appears to be absent in bdelloid rotifers. Which of these, if found in this group, would bring into question the idea that they reproduce ONLY asexually? A) female rotifers with eggs B) significant differences of two different alleles among different populations (one population having mostly allele A and one having mostly a). C) cells in which meiosis occurs D) related groups (not bdelloid rotifers) which reproduce both sexually and asexually.
cells in which meiosis occurs
Sister chromatids are joined at the ________. A) centromere B) spindle C) centrosome D) centriole
centromere
What is the name of the microtubule-organizing center found in animal cells? A) centriole B) centrosome C) centromere D) kinetochore
centrosome
During metaphase, ________. A) the nuclear envelope breaks up B) sister chromatids separate C) centromeres divide D) chromosomes line up in the middle of the cell
chromosomes line up in the middle of the cell
The drug cytochalasin B blocks the function of microfilaments. Which of the following aspects of the animal cell cycle would be most disrupted by cytochalasin B? A) spindle formation B) spindle attachment to centromeres C) movement of chromosomes to the poles of the cell during anaphase D) cleavage furrow formation and cytokinesis
cleavage furrow formation and cytokinesis
During which of the following processes do sister chromatids separate from each other? A) during meiosis I only B) during meiosis II only C) during both mitosis and meiosis I D) during both mitosis and meiosis II
during both mitosis and meiosis II
A karyotype would be unable to determine ________. A) sex B) Down syndrome C) Turner syndrome D) eye color
eye color
How much genetic material is present in a cell during prophase I compared to a cell that has completed meiosis II? A) one-quarter as much B) four times as much C) one-half as much D) twice as much
four times as much
Crossing over during prophase I results in ________. A) nondisjunction B) reciprocal translocation C) duplication D) genetic recombination
genetic recombination
A cell that completed the cell cycle without undergoing cytokinesis would ________. A) have less genetic material than it started with B) not have completed anaphase C) have its chromosomes lined up in the middle of the cell D) have two nuclei
have two nuclei
During metaphase I, ________. A) crossing over occurs B) homologous chromosomes line up in the middle of the cell C) the nuclear envelope breaks up D) sister chromatids separate and migrate to opposite poles
homologous chromosomes line up in the middle of the cell
Scientists obtain cells in various phases of the cell cycle. They obtain a group of cells that have 1 1/2 times more DNA than G1 phase cells. The cells are most likely ________. A) between the G1 and S phases in the cell cycle B) in the G2 phase of the cell cycle C) in the M phase of the cell cycle D) in the S phase of the cell cycle
in the S phase of the cell cycle
A karyotype ________. A) is a display of all of the cell types in an organism. B) is an organized picture of a cell's chromosomes. C) reveals the appearance of an organism. D) is a display of a cell's mitotic stages.
is an organized picture of a cell's chromosomes
Crossing over of chromosomes normally takes place during which of the following processes? A) meiosis II B) meiosis I C) mitosis D) mitosis and meiosis II
meiosis I
This diagram of the human life cycle shows that ________. A) meiosis produces a diploid zygote B) meiosis produces haploid sperm and egg cells C) fertilization produces a haploid zygote D) a diploid zygote undergoes meiosis to produce an adult human
meiosis produces haploid sperm and egg cells
The above figure shows that ________. A) meiosis results in the formation of four haploid daughter cells B) fertilization results in four haploid daughter cells C) the human 2n number is 4 D) meiosis forms diploid gametes
meiosis results in the formation of four haploid daughter cells
Karyotypes are usually prepared from cells in which stage of mitosis? A) prophase B) metaphase C) anaphase D) interphase
metaphase
Which is NOT associated with sexual reproduction? A) meiosis B) mitosis C) fertilization D) the exchange of chromosomes between organisms of different species
mitosis
One difference between mitosis and meiosis is ________. A) mitosis produces cells genetically identical to the parent cell, but meiosis does not B) mitosis produces more daughter cells for each division than meiosis C) mitosis produces haploid cells, but meiosis produces diploid cells D) mitosis requires only one parent cell, but meiosis requires two parent cells
mitosis produces cells genetically identical to the parent cell, but meiosis does not
How many chromosomes can a gamete possess as a result of nondisjunction? A) n + 1 or n - 1 B) 2n + 1 or 2n - 1 C) 2n - 1 only D) 2n + 1 or n - 1
n + 1 or n - 1
Most _______ and _______ cells of the body are in a permanently non-dividing state A) bone; cartilage B) skin; liver C) nerve; muscle D) bone; live
nerve; muscle
Amanda's abnormal number of sex chromosomes resulted from ________. A) independent assortment of chromosomes B) crossing over C) nondisjunction D) random fertilization
nondisjunction
G1 is associated with which cellular events? A) normal growth and cell function B) DNA replication C) the beginning of mitosis D) break down of the nuclear membrane
normal growth and cell function
The chromosomes of eukaryotic cells are found in the ________. A) nucleus B) centriole C) Golgi apparatus D) nucleolus
nucleus
As shown in the following figure, plant cell cytokinesis differs from animal cell cytokinesis because ________. A) plant cells produce more daughter cells B) plant cells form a cell plate and animal cells do not C) animal cells produce more daughter cells D) animal cells form a cell plate and plant cells do not
plant cells form a cell plate and animal cells do not
Ordinary cell division produces two daughter cells that are genetically identical. This type of cell division is important for all of the following functions EXCEPT ________. A) growth of a multicellular organism B) cell replacement C) production of sperm and eggs D) asexual reproduction
production of sperm and eggs
When chiasmata are seen in cells using a microscope, the cells are most likely in which stage of meiosis? A) prophase II B) anaphase II C) prophase I D) anaphase I E) metaphase II
prophase I
The CORRECT sequence of stages of mitosis is ________. A) prophase, metaphase, anaphase, telophase B) telophase, prophase, anaphase, metaphase C) anaphase, interphase, prophase, metaphase, telophase D) interphase, prophase, metaphase, anaphase, telophase
prophase, metaphase, anaphase, telophase
Which of these describes the type of reproduction that is most adaptive in a rapidly changing environment with many different parasitic diseases present? A) asexual reproduction because the currently successful genotypes can reproduce quickly B) asexual reproduction, because asexual reproduction uses less energy, which leaves more for each individual to adapt to the changing environment C) sexual reproduction because the diversity of genotypes increases the likelihood that there is one which can survive in a new environment D) sexual reproduction because this type of reproduction allows the production of a greater number of offspring thus providing more individuals to take advantage of any environmental challenges presented
sexual reproduction because the diversity of genotypes increases the likelihood that there is one which can survive in a new environment
A duplicated chromosome consists of two ________. A) centromeres B) centrosomes C) genomes D) sister chromatids
sister chromatids
Which of the following processes occurs in meiosis but not in mitosis? A) chromosome replication B) synapsis of chromosomes C) alignment of chromosomes in the middle of the cell D) condensation of chromosomes
synapsis of chromosomes
Cytokinesis typically begins during the ________ stage of mitosis. A) telophase B) prophase C) metaphase D) anaphase
telophase
Which of the following is a stage of mitosis? A) cytokinesis B) telophase C) interphase D) DNA synthesis
telophase
Anaphase II is essentially the same as mitotic anaphase except that in anaphase II ________ and in mitotic anaphase ________. A) the cells are diploid... the cells are haploid B) chromosomes line up double file in the middle of the cell... chromosomes line up single file in the middle of the cell C) crossing over occurs... crossing over does not occur D) the cells are haploid and sister chromatids separate... the cells have the same number of chromosomes as the original cell and sister chromatids separate
the cells are haploid and sister chromatids separate... the cells have the same number of chromosomes as the original cell and sister chromatids separate
Genetic variation is accomplished by all but one of the following. Choose the exception. A) the events of meiosis I B) crossing over C) independent assortment D) the events of meiosis II
the events of meiosis II
During telophase, ________. A) the events of prophase are reversed B) chromosomes line up in the middle of the cell C) sister chromatids become separate chromosomes D) the nuclear envelope breaks up
the events of prophase are reversed
Taxol is an anticancer drug extracted from the Pacific yew tree. In animal cells, Taxol prevents microtubule disassembly. Thus, Taxol stops mitosis by interfering with which of the following structures or processes? A) the mitotic spindle B) cytokinesis C) nuclear envelope D) chromosome condensation
the mitotic spindle
The karyotype above shows ________. A) abnormal sex chromosomes B) trisomy 21, a cause of Klinefelter syndrome C) Turner syndrome D) trisomy 21, a cause of Down syndrome
trisomy 21, a cause of Down syndrome
The 2n number for the cell depicted here is ________. A) one B) two C) four D) eight
two
The mitotic cell cycle results in the production of ________. A) four cells, each with the same amount of genetic material and the same genetic information B) two cells, each with the same amount of genetic material but with different genetic information C) two cells, each with the same amount of genetic material and the same genetic information D) four cells, each with the same amount of genetic material but with different genetic information
two cells, each with the same amount of genetic material and the same genetic information
Upon completion of telophase I and cytokinesis, there is(are) ________ cell(s). A) four haploid B) two diploid C) two haploid D) one diploid
two haploid