Zhong Biology 1020 Chapter 13

Terms in this set (51)

Only _____ cells contain two sets of chromosomes, one maternal and one paternal.

Homologous chromosomes move toward opposite poles of a dividing cell during

_______is the complete set of an organism's genes

_______ ____ is the exchange of homologous portions of nonsister chromatids

Synapsis occurs.

Which of the following occurs during meiosis but not during mitosis?
Chromosomes condense.
A spindle apparatus forms.
Synapsis occurs.
Chromosomes migrate to opposite poles.
Chromosomes align at the metaphase plate.

The pairing of homologous chromosomes that only occurs during prophase I of meiosis is called

The pairing of homologous chromosomes that only occurs during_________ of meiosis is called synapsis.

The pairing of homologous chromosomes that only occurs during prophase I of ________is called synapsis.

It has half the amount of DNA as the cell that began meiosis.

If a cell has completed the first meiotic division and is just beginning meiosis II, which of the following is an appropriate description of its contents?
It has one-fourth the DNA and one-half the chromosomes as the originating cell.
It is identical in content to another cell from the same meiosis.
It has half the chromosomes but twice the DNA of the originating cell.
It has half the amount of DNA as the cell that began meiosis.
It has the same number of chromosomes but each of them has different alleles than another cell from the same meiosis.

Homologous chromosomes of a pair are separated from each other.

Which of the following happens at the conclusion of meiosis I?
Sister chromatids are separated.
Homologous chromosomes of a pair are separated from each other.
Cohesins are cleaved at the centromeres.
Four daughter cells are formed.
The chromosome number per cell is conserved.

When we see chiasmata under a microscope, that lets us know which of the following has occurred?
prophase I
meiosis II
separation of homologs
anaphase II
asexual reproduction

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
2x.
0.25x.
4x.
x.
0.5x.

How many different combinations of maternal and paternal chromosomes can be packaged in gametes made by an organism with a diploid number of 8 (2n = 8)?
8
16
32
2
4

sister chromatids separate during anaphase.

Meiosis II is similar to mitosis in that
sister chromatids separate during anaphase.
homologous chromosomes synapse.
the daughter cells are diploid.
DNA replicates before the division.
the chromosome number is reduced

produces offspring genetically identical to the parent

Asexual reproduction _____.
is limited to plants
is limited to single-cell organisms
leads to a loss of genetic material
produces offspring genetically identical to the parent
requires both meiosis and mitosis

Homologous chromosomes contain the same gene loci but may have different alleles of a particular gene. Sister chromatids are identical copies of each other produced during DNA replication.

How are sister chromatids and homologous chromosomes different from each other?
They are not different. Homologous chromosomes and sister chromatids are both identical copies of each other.
Homologous chromosomes are closely associated with each other in both mitosis and meiosis. Sister chromatids are only associated with each other during mitosis.
Homologous chromosomes are identical copies of each other. One sister chromatid comes from the father, and one comes from the mother.
Homologous chromosomes contain the same gene loci but may have different alleles of a particular gene. Sister chromatids are identical copies of each other produced during DNA replication.
Sister chromatids are only formed during mitosis. Homologous chromosomes are formed during meiosis.

Each cell has eight homologous pairs.

Which of the following is true of a species that has a chromosome number of 2n = 16?
The species has 16 sets of chromosomes per cell.
The species is diploid with 32 chromosomes per cell.
A gamete from this species has four chromosomes.
During the S phase of the cell cycle there will be 32 separate chromosomes.
Each cell has eight homologous pairs.

an error in either egg or sperm meiotic anaphase

Which of the following might result in a human zygote with 45 chromosomes?
failure of the egg nucleus to be fertilized by the sperm
an error in the alignment of chromosomes on the metaphase plate
lack of chiasmata in prophase I
fertilization of a 23 chromosome human egg by a 22 chromosome sperm of a closely related species
an error in either egg or sperm meiotic anaphase

DNA content is halved in both meiosis I and meiosis II. Ploidy level changes from diploid to haploid in meiosis I, and remains haploid in meiosis II.

The parent cell that enters meiosis is diploid, whereas the four daughter cells that result are haploid.
Which statement correctly describes how cellular DNA content and ploidy levels change during meiosis I and meiosis II?
DNA content is halved in both meiosis I and meiosis II. Ploidy level changes from diploid to haploid only in meiosis II.
DNA content is halved in both meiosis I and meiosis II. Ploidy level changes from diploid to haploid in meiosis I, and remains haploid in meiosis II.
DNA content is halved only in meiosis I. Ploidy level changes from diploid to haploid only in meiosis II.
DNA content is halved only in meiosis II. Ploidy level changes from diploid to haploid in meiosis I, and remains haploid in meiosis II.
DNA content is halved only in meiosis I. Ploidy level changes from diploid to haploid in meiosis I, and remains haploid in meiosis II.

During _______ of both meiosis I and meiosis II, the DNA content (number of copies of chromosomes) in a cell is halved.

Meiosis I produces _____ cells, each of which is _____.

Meiosis II typically produces _____ cells, each of which is _____.

During __________sister chromatids separate and migrate to opposite poles.

telophase II and cytokinesis.

Four haploid cells are present at the end of

telophase I and cytokinesis

At the end of _______________there are two haploid cells.

Homologous chromosomes pair during

During ___________ tetrads align along the metaphase plate.

Synapsis, the pairing of homologous chromosomes, occurs during ___________.

Homologous chromosomes migrate to opposite poles during _____.

During _____ chromosomes align single file along the equator of a haploid cell.

During _____ a spindle forms in a haploid cell.

During _______ the centrosome duplicates and the chromosomes are not condensed.

Mitosis, meiosis

______ goes on continuously in most parts of the body, whereas ______takes place only in the gonads.

________ is the only time that chromosomes line up by homologous pairs.

The _______is the point of attachment between two duplicated chromosomes.

the complete set of an organism's genes and other DNA sequences

Which of the following defines a genome?
a karyotype
the complete set of an organism's genes and other DNA sequences
the complete set of an organism's polypeptides
the complete set of a species' polypeptides

Asexual reproduction occurs during _____.
chromosome exchange between organisms of different species
mitosis
fertilization
meiosis

In sexual reproduction, individuals transmit half of their nuclear genes to each of their offspring.

Which of the following is a true statement about sexual vs. asexual reproduction?
Asexual reproduction, but not sexual reproduction, is characteristic of plants and fungi.
Asexual reproduction produces only haploid offspring.
In sexual reproduction, individuals transmit half of their nuclear genes to each of their offspring.
In asexual reproduction, offspring are produced by fertilization without meiosis

carry information for the same traits

Homologous chromosomes _____.
align on the metaphase plate in meiosis II
carry information for the same traits
carry the same alleles
are identical

haploid, and the chromosomes are each composed of two chromatids

After telophase I of meiosis, the chromosomal makeup of each daughter cell is _____.
diploid, and the chromosomes are each composed of two chromatids
haploid, and the chromosomes are each composed of a single chromatid
diploid, and the chromosomes are each composed of a single chromatid
haploid, and the chromosomes are each composed of two chromatids

half the number of chromosomes and one-fourth the amount of DNA.

How do cells at the completion of meiosis compare with cells that are in prophase of meiosis I? They have _____.
half the number of chromosomes and one-fourth the amount of DNA.
the same number of chromosomes and half the amount of DNA.
half the amount of cytoplasm and twice the amount of DNA.
half the number of chromosomes and half the amount of DNA.

Homologous chromosomes of a pair are separated from each other.

Which of the following happens at the conclusion of meiosis I?
Sister chromatids are separated.
The chromosome number per cell remains the same.
Four daughter cells are formed.
Homologous chromosomes of a pair are separated from each other.

mitosis and meiosis II

Sister chromatids separate from each other during _____.
meiosis II only
mitosis and meiosis II
mitosis and meiosis I
meiosis I only

Diploid cells form haploid cells.

Which of the following can occur by the process of meiosis but not mitosis?
A diploid cell combines with a haploid cell.
Haploid cells multiply into more haploid cells.
Haploid cells fuse to form diploid cells.
Diploid cells form haploid cells.

Sister chromatids separate in mitosis, while homologous pairs of chromosomes separate in meiosis I.

What is a major difference between mitosis and meiosis I in a diploid organism?
Sister chromatids separate in mitosis, while homologous pairs of chromosomes separate in meiosis II.
Sister chromatids separate in mitosis, while homologous pairs of chromosomes separate in meiosis I.
DNA replication takes place prior to mitosis, but not before meiosis I.
Only meiosis I results in daughter cells that contain identical genetic information.

Crossing over normally takes place during which of the following processes?

Centromeres split and sister chromatids migrate to opposite poles in meiosis _____.

the random way each pair of homologous chromosomes lines up at the metaphase plate during meiosis I

Independent assortment of chromosomes is a result of _____.
the random way each pair of homologous chromosomes lines up at the metaphase plate during meiosis I
the random combinations of eggs and sperm during fertilization
the diverse combination of alleles that may be found within any given chromosome
the random distribution of the sister chromatids to the two daughter cells during anaphase II

Independent assortment of chromosomes occurs during _____.

Corresponding segments of non-sister chromatids are exchanged.

When homologous chromosomes cross over, what occurs?
Corresponding segments of non-sister chromatids are exchanged.
Two sister chromatids exchange identical pieces of DNA.
Two chromatids get tangled, resulting in one re-sequencing its DNA.
Maternal alleles are "corrected" to be like paternal alleles and vice versa.

Sexual reproduction results in many new gene combinations, some of which will lead to differential reproduction.

How is natural selection related to sexual reproduction as opposed to asexual reproduction?
Sexual reproduction allows the greatest number of offspring to be produced.
Sexual reproduction utilizes far less energy than asexual reproduction.
Sexual reproduction results in the greatest number of new mutations.
Sexual reproduction results in many new gene combinations, some of which will lead to differential reproduction.

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