College Bio Chapter 9
Meiosis 1
(2N) looks similar to mitosis, but the homologous chromosomes pair up to form tetrads during prophase and crossing over happens; during metaphase, chromosomes line up in the middle; During anaphase, the tetrads are pulled apart into sister chromatids; during telophase, the cell is pinched.
Diploid
(2n); normal paired chromosomes where our cells are
Haploid
(n); not paired
Nonsister chromatids
(same as homologous chromosomes) one from mom, one from dad
Differences between Meiosis I and II
1 to 2/2 to 4; S phase/no s phase; tetrats/no tetrads; crossing over/no crossing over; anaphase-1 & 1^1, 2 & 2^1 are pulled apart/anaphase- 1, 1^1, 2, 2^1 are all pulled apart separately; pulls sister chromatids together/pulls separate chromatids together
Differences between Mitosis and Meiosis
2 identical cells/4 different cells; diploid/haploid; regular cells/sex cells; No crossing over/crossing over occurs; unlimited splits/splits twice; doesn't form tetrads/forms tetrads; no variation/variation; 1 phase/2 phases
Variation for each parent
2^23
13 - for the figure shown here, indicate the correct stage of meiosis and the diploid number of the cell A) prophase II, 2n=4 B) anaphase II, 2n=2 C) prophase I, 2n=4 D) metaphase II, 2n=2 E) metaphase I, 2n=4
A
An individual with the karyotype 48, XYYY woul dhave how many Barr bodies A) 0 B) 1 C) 2 D) 3 E) 4
A
During meiosis I the homologous chromosomes of a tetrad A) face opposite spindle poles B) do not face spindle poles but are aligned at the spindle equator C) face the same spindle pole D) undergo separation of sister chromatids E) face both spindle poles
A
Following meiosis I, the daughter cells are ___; following meiosis II, the daughter cells are ___; and following mitosis, the daughter cells are ___ A) haploid; haploid; diploid B) diploid; haploid; diploid C) diploid; diploid; diploid D) diploid; diploid; haploid E) haploid; haploid; haploid
A
In the human life cycle, A) meiosis produces haploid gametes, and fertilization creates a diploid cell that divides by mitosis to produce a new individual B) a haploid zygote reproduces by meiosis to produce diploid daughter cells that divide by mitosis to produce a new individual C) diploid gametes reproduce by meiosis to produce haploid daughter cells that divide by mitosis to produce a new individual D) diploid gametes reproduce by mitosis to produce diploid daughter cells that divide by meiosis to produce a new individual E) mitosis produces haploid gametes and fertilization creates a diploid cell that divides by meiosis to produce a new individual
A
It is essential that germ cells undergo meiosis so that A) the number of chromosomes is cut in half in gametes B) genetic disorders are prevented C) genetic diversity is reduced D) the fertilized egg has half the genetic material of the parents E) the cells can differentiate
A
Which of the following processes does not contribute to creating genetic variability in the offspring? A) interkinesis B) pairing of homologous chromosomes C) crossing-over D) independent assortment of chromosomes E) having different alleles of the same gene
A
Which statement best describes hwo the members of a tetrad are separated during meiosis I? A) the two homologous chromosomes of a tetrad separate into different daughter nuclei B) the two homologous chromosomes of a tetrad are duplicated and separate into each daughter nucleus C) the nonsister chromatids of each tetrad separate into different daughter nuclei D) the two homologous chromosomes of a tetrad separate into one of two daughter nuclei E) the sister chromatids of each chromosome separate into different daughter nuclei
A
15 - for the figure shown here, indicate the correct stage of meiosis and diploid chromosome number A) metaphase II, 2n=4 B) metaphase I, 2n=4 C) metaphase II, 2n=2 D) metaphase I, 2n=8 E) metaphase II, 2n=8
B
A tetrad is composed of A) two sister chromatids with separate centromeres B) two chromosomes with two sister chromatids each C) four chromosomes with two sister chromatids each D) four sister chromatids attached at a common centromere E) four sister chromatids, each with its own centromere
B
During meiosis II, A) homologous chromosomes line up separately, with sister chromatids facing opposite spindle poles B) chromosomes line up separately, with sister chromatids facing opposite spindle poles C) chromosomes line up separately, with sister chromatids facing the same spindle pole D) homologous chromosomes line up separatey, with sister chromatids facing the same spindle pole E) homologous chromosomes line up together, with sister chromatids facing opposite spindle poles
B
During prophase II, a diploid organism contains how many copies of each gene? A) 3 B) 2 C) 8 D) 4 E) 1
B
Interphase differs from interkinesis because A) homologous chromosomes separate during interkinesis, but not during interphase B) DNA is duplicated during interphase, but not during interkinesis C) homologous chromosomes separate during interphase, but not during interkinesis D) interkinesis only occurs during mitosis, while interphase occurs during both meiosis and mitosis E) dna is duplicated during interkinesis, but not during interphase
B
Metaphase II is more similar to metaphase of mitosis than to metaphase I because A) in metaphase I, tetrads align together at the spindle equator B) in metaphase II, dyads align separately at the spindle equator C) in metaphase I, dyads align separately at the spindle equator D) in metaphase of mitosis, tetrads align separately at the spindle equator E) in metaphase II, tetrads align separately at the spindle equator
B
The possibility of Down syndrome increases as the mother's age increases because A) fertilization no longer occurs correctly with older eggs B) the possibility of nondisjunction increases C) her dna is damaged through an accumulation of replication occurs D) the contents of the egg contain the wrong signals for the correct development of the fetus E) her dna stops for replication errors
B
Turner syndrome is associated with which of the following karyotypes? A) 47, XXY B) 45, XO C) 47, XY, trisomy 21 D) 46, XY E) 47, XXX
B
Which of the following human syndromes is monosomy? A) swyer syndrome B) turner syndrome C) down syndrome D) barr body syndrome E) klinefelter syndrome
B
Which of the following statements is correct? A) mitosis involves one division and produces two nonidentical daughter nuclei B) meiosis involves two divisions and produces four nonidentical daughter nuclei C) meiosis involves two divisions and produces four identical daughter nuclei D) mitosis involves two divisions and produces four identical daughter nuclei E) meiosis involves one division and produces two nonidentical daughter nuclei
B
A dyad consists of A) two homologous chromosomes consisting of a single DNA strand each B) one duplicated chromosome consisting of two nonsister chromatids C) one duplicated chromosome consisting of two sister chromatids D) two homologous chromosomes consisting of two sister chromatids E) two homologous chromosomes consisting of two nonsister chromatids
C
An individual with Swyer syndrome (46,XY) differs from an individual with Klinefelter syndrome (47, XXY) because A) neither individual has a functional SRY gene, but the X chromosome individual with Swyer syndrome has a functional SRY and appears male B) an individual with Swyer syndrome lacks a functional SRY gene, but appears male because it has moved to the X chromosome as in an individual with Klinefelter syndrome C) an individual with Klinefelter syndrome has a functional SRY gene on his Y chromosome, whereas an individual with Swyer syndrome does not. D) an individual with Swyer syndrome has a Barr body, while an individual with Klinefelter syndrome does not. E) both individuals have a functional SRY gene, but the extra X chromosome makes the individual with Klinefelter syndrome appear female
C
Armadillos have a diploid chromosome number of 64. At prophase I, an armadillo's cell would have ___ tetrads present A) 80 B) 128 C) 32 D) 16 E) 64
C
Camels have a diploid chromosome number of 70. At prophase II, each cell would contain how many tetrads? A) 35 B) 280 C) 0 D) 140 E) 70
C
During G1 stage of interphase a diploid organism contains how many copies of each gene? A) 8 B) 1 C) 2 D) 16 E) 4
C
During which stage of meiosis will the pairs of homologous chromosomes line up? A) anaphase I B) prophase II C) metaphase I D) metaphase E) metaphase II
C
One major difference between meiosis I and meiosis II is that A) in telophase of meiosis I, four daughter cells form from the parent cell, and in telophase of meiosis II, each parent cell gives rise to two daughter cells B) in meiosis I, there is no pairing of chromosomes while homologous pair in meiosis II C) crossing-over occurs in prophase of meiosis I, but not in prophase of meiosis II D) sister chromatids are separated during meiosis 1, while homologous chromosomes are separated during meiosis II E) the resulting cells at the end of meiosis I are diploid, while the cells at the end of meiosis II are haploid
C
Swyer syndrome (46, XY, female appearance) would most likely result from A) nondisjunction during meiosis I in the male parent B) nondisjunction during meiosis I in the female parent C) normal disjunction during meiosis, but delection of a portion of the Y chromosome in the male parent D) nondisjunction during meiosis II in the male parent E) nondisjunction during meiosis II in the female parent
C
The failure of sister chromatids to separate would result in how many normal gametes? A) 0 B) 1 C) 2 D) 3 E) 4
C
Which of the following does not occur twice during meiosis A) alignment of chromosomes at the spindle equator B) spindle formaiton C) pairing of homologous chromosomes D) production of daughter nuclei E) separation of genetic material
C
Which of the following is a correct match? A) synapsis - prophase II B) separation of sister chromatids - anaphase I C) separation of sister chromatids - anaphase II D) separation of tetrads - anaphase II E) synapsis - metaphase I
C
Which of the following is not correct about crossing-over? A) crossing-over during prophase I when homologous chromosomes line up prior to separation B) crossing-over is preceeded by a process known as synapsis, where homologous chromosomes attach to eachother C) crossing-over is only detectable when it occurs between sister chromatids D) crossing-over results in greater genetic variability in offspring E) in human, crossing-over occurs an average of approximately two events per chromosomes
C
Which of the following lists is in the correct order, from the least inclusive to the most inclusive? A) allele- chromosome - gene B) allele - gene - chromosome C) gene - allele - chromosome D) gene - chromosome - allele E) chromosome - gene - allele
C
9 - which of the diagrams represent a chromosome or chromosomes pair in a cell at the end of prophase II? A) diagram 1 B) diagram 2 C) diagram 3 D) diagram 4 E) diagram 5
D
Crossing-over between sister chromatids does not result in recombination of genetic material, while crossing-over between nonsister chromatids does because A) sister chromatids have the same alleles but different genes, while nonsister chromatids have different alleles but the same genes B) sister chromatids have the same genes, while nonsister chromatids have different ones C) nonsister chromatids have the same alleles, while sister chromatids have different ones D) sister chromatids have the same alleles, while nonsister chromatids have different one E) nonsister chromatids have the same genes, while sister chromatids have different ones
D
Goats have a diploid chromosome number of 60. At prophase I, each cell would have ___ tetrads present, for a total of ___ chromatids A) 30; 60 B) 30; 240 C) 60; 240 D) 30; 120 E) 60; 120
D
Klinefelter syndrome can result from nondisjunction during A) meiosis I in the male parent B) meiosis I in the female parent C) meiosis I or II in the male parent D) meiosis I or II in either parent E) meiosis I in either female parent
D
Which of the following phases results in separation of sister chromatids into daughter chromosomes? A) anaphase I, anaphase II, and anaphase of mitosis B) anaphase of mitosis C) anaphase I and anaphase of mtiosis D) anaphase II and anaphase of mitosi E) anaphase I and anaphase II
D
Which of the following statements is true? A) while sex chromosomes determine different genders, they look the same until they are stained B) homologous chromosomes differ in banding patterns, the traits they code for, and size C) in all 46 chromosomes have an identical match called the homologue D) chromosomes are classified into two categories; the sex chromosomes that determine gender and autosomes that determine non-gender traits E) chromosomes are classified into two categories: autosomes that determine gender and the sex chromosomes that determine non-gender related traits
D
You are looking at a cell under a microscope and see what appears to be several "X" structures being pulled to each side of the cell. What stage of meiosis are you looking at? A) prophase II B) metaphase I C) anaphase II D) anaphase I E) prophase I
D
A human egg with 22 chromosomes that is fertilized by a normal sperm will result in A) a zygote with trisomy B) a zygote with disomy C) nondisjunction during subsequent mitosis D) a zygote with normal chromosome number E) a zygote with monsomy
E
All but which one of the following results from nondisjuction A) down syndrome B) trisomy C) polyploidy D) monosomy E) diploidy
E
Camels have a diploid chromosome number of 70. At prophase II, each cell would contain how many chromatids? A) 0 B) 280 C) 35 D) 140 E) 70
E
During prophase I, a diploid organism contains how many copies of each gene? A) 3 B) 2 C) 8 D) 1 E) 4
E
In each gamete following telophase II, how many copies of each gene is/are present A) 4 B) 2 C) 3 D) 8 E) 1
E
It would be possible for a male and a female to have exactly the same ___, but they would have to differ in ___ A) homologues; autosomes B) karyotype; sex chromosomes C) karyotype; autosomes D) diploid chromosomes; haploid chromosomes E) autosomes; sex chromosomes
E
The human life cycle consists of A) adults that are diploid who produces zygotes that are also diploid B) gametes that are diploid and produce haploid zygotes; these grow into haploid adults C) adults who are haploid and produce diploid gametes; these gametes fuse to produce a haploid zygote which grows into an adult D) zygotes who are haploid refuse to produce a diploid gamete which grows into an adult E) adults who are diploid and produce haploid gametes; these gametes fuse to produce a diploid zygote which grows into an adult
E
Which of the following is not a function of meiosis A) produce gametes B) reduce the chromosome number in gametes C) create genetic variability D) keep the chromosome number constant from one generation to the next E) cause an organism to grow
E
Which of the following is not a symptom of down syndrome? A) short stature B) eyelid fold C) fissured tongue D) stubby fingers E) tall structure
E
Which of the following processes and products are paired correctly? A) spermatogenesis - 2n zygote B) mitosis - 1n gamete C) meiosis - 2n zygote D) oogenesis - 2n zygote E) oogenesis - 1n gamete
E
the failure of sister chromatids to separate during meiosis is called A) crossing-over B) disjunction C) synapsis D) tetrad formation E) nondisjunction
E
Meiosis II
G2 and G1 of interphase, but no S phase because DNA is not doubled; No tetrads are formed in prophase II; sister chromatids are lined up in the middle during metaphase; sister chromatids are pulled apart into single chromatids in anaphase II (haploids); in telophase II, the singles are separated into four different haploid cells.
Sister Chromatids (dyad)
formed during the S phase, exact copies (from the same parent)
Aneuploidy
incorrect number of chromosomes
Oogenesis
making the egg
Spermatogenesis
making the sperm
Oogenesis description
one cell that starts as 2n and splits into a functional cell and a polar body, then splits the same way again if the egg is fertilized. Oogenesis always goes through meiosis I, but not always meiosis II. Only one cell that is n is ready.
Spermatogenesis description
one cell that starts as 2n that goes through Mitosis I and II to form four functional sperm cells that are n
Monosomy
one chromosome
Homologous Chromosome (homologues)
one from mom, one from dad (set)
Karyotype
picture of chromosomes; see if chromosomes are normal/correct number
Meiosis 2
second split
Meiosis
sexual reproduction; every cell is different
X-Inactivation (Barr body)
switching what chromosome is dominent
14 - for the figure shown here, indicate the correct stage of meiosis and diploid chromosome number A) anaphase II, 2n=4 B) anaphase 1, 2n=8 C) anaphase II, 2n=8 D) anaphase I, 2n=16 E) anaphase II, 2n=16
B
Chromosomes that occur in pairs and code for the same traits are called ___ chromosomes; these do not include the ___ chromosomes, which code for gender A) homologous; sex B) homologous; autosomes C) autosomes; homologous D) sex; autosomes E) diploid; haploid
a
8 - which of the diagrams best illustrates the appearance of a chromosome or chromosome pair at the end of prophase I? A) diagram 1 B) diagram 2 C) diagram 3 D) diagram 4 E) diagram 5
b
Euploidy
correct number of chromosomes
During crossing over, A) sister chromatids from each homologous chromosome of a tetrad are exchanged, resulting in new combinations of alleles B) one homologous chromosome of a tetrad is exchanged with another tetrad, resulting in new combinations of alleles C) genetic material is exchanged between sister chromatids, resulting in new combinations of alleles D) nonsister chromatids from each homologous chromosome of a tetrad are exchanged, resulting in a new combination of alleles E) genetic material is exchanged between nonsister chromatids, resulting in a new combination of alleles
e
Zygote
fertilized egg
Meiosis 1
first split
Synapsis
forms a tetrad (bivalent)
Allele
the different expression of the gene
Trisomy
three chromosomes
Down Syndrome
three sets of the 21st chromosome (trisomy)
Gene
traits
