Chapter 13
Two sister chromatids are joined at the centromere prior to meiosis. Which statement is correct?
Barring mutation, the two sister chromatids must be identical.
Which of the following results when homologous chromosomes cross over in meiosis?
Corresponding segments of non-sister chromatids are exchanged.
Which of the following processes occur during meiosis but not mitosis?
Diploid cells form haploid cells.
Which of the following statements describes one characteristic of each chromosome in a cell during the entire process of meiosis I?
Each chromosome consists of two sister chromatids joined by a centromere.
Which of the following statements is true of a species that has a chromosome number of 2n = 16?
Each diploid cell has eight homologous pairs of chromosomes.
A (hypothetical) diploid organism has different genes that control wing color and wing length. A female of this species has a paternal chromosome set containing one orange-wing allele and one long-wing allele and a maternal set containing one blue-wing allele and one short-wing allele. Which of the following types of eggs would she be expected to produce after meiosis?
Each egg has a one-fourth chance of having either blue long, blue short, orange long, or orange short combinations
Measurements of the amount of DNA per nucleus were taken on a large number of cells from a growing fungus. The measured DNA levels ranged from 3 to 6 picograms (pg) per nucleus. During the entirety of which stage of the cell cycle did the nucleus contain 6 pg of DNA?
G2
Which of the following statements correctly describes how sister chromatids and homologous chromosomes differ from each other?
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.
Which of the following events happens at the conclusion of meiosis I?
Homologous chromosomes of a pair are separated from each other.
Cells from a diploid protist with n=1 are followed through mitosis and meiosis. The drawings in the figure below represent the chromosomes. Refer to the drawings and answer the following question. Which diagram represents anaphase I of meiosis?
I
Multiple cells from the same species were isolated, the relative cohesion protein content for each type was determined, and the results were plotted on the graph. Refer to the graph to answer the following question. Which sample is consistent with a cell that is in telophase I?
I
For the following question, match the key event of meiosis with the stages listed below. I. Prophase IV. Prophase IIII. Metaphase IVI. Metaphase IIIII. Anaphase IVII.Anaphase IIIV. Telophase IVIII.Telophase II
II
Multiple cells from the same species were isolated, the relative cohesion protein content for each type was determined, and the results were plotted on the graph. Refer to the graph to answer the following question. Which sample is consistent with a cell that is entering mitosis?
II
Multiple cells from the same species were isolated, the relative cohesion protein content for each type was determined, and the results were plotted on the graph. Refer to the graph to answer the following question.Which sample is consistent with a cell that is in metaphase I?
II
Cells from a diploid protist with n=1 are followed through mitosis and meiosis. The drawings in the figure below represent the chromosomes. Refer to the drawings and answer the following question.
III
Multiple cells from the same species were isolated, the relative cohesion protein content for each type was determined, and the results were plotted on the graph. Refer to the graph to answer the following question. Which sample is consistent with a cell that has completed meiosis?
III
Multiple cells from the same species were isolated, the relative cohesion protein content for each type was determined, and the results were plotted on the graph. Refer to the graph to answer the following question. Which sample is consistent with a cell that has completed mitosis?
III
For the following question, match the key event of meiosis with the stages listed below. I. Prophase IV. Prophase IIII. Metaphase IVI. Metaphase IIIII. Anaphase IVII.Anaphase IIIV. Telophase IVIII.Telophase II Haploid cells form containing joined sister chromatids.
IV
Which of the following explanations correctly describes a reproductive approach?
In asexual reproduction, a single individual is the sole parent and passes copies of its genes to its offspring without the fusion of gametes.
Which of the following statements about reproduction is correct?
In sexual reproduction, individuals transmit half of their nuclear genes to each of their offspring.
Which of the following statements about the human X chromosomes is correct?
It carries genes that influence an individual's biological sex.
A cell has completed meiosis I and the first cytokinesis, and is just beginning meiosis II. Which of the following statements describes its genetic contents?
It has half the amount of DNA as the cell that began meiosis.
Which of the following statements correctly describes a karyotype?
It is an organized image of a cell's chromosomes.
A particular organism has 46 chromosomes in its karyotype. Which of the following statements is correct regarding this organism?
It produces gametes with 23 chromosomes.
Which of the following statements describes a major difference between meiosis II and mitosis in a diploid animal?
Meiosis II occurs in a haploid cell, while mitosis occurs in diploid cells.
Which of the following phases make up the stages of mitosis?
Prophase, prometaphase, metaphase, anaphase, and telophase
Genetic variation leads to genetic diversity in populations and is the raw material for evolution. Which of the following statements best represents the connection between reproduction and evolution?
Sexual reproduction increases genetic variation because random mutations can be shuffled between organisms.
How does natural selection apply to sexual reproduction as opposed to asexual reproduction?
Sexual reproduction results in new gene combinations, some of which will have increased reproductive fitness.
Which of the following statements describes 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 I.
Two different species of protists living in a tide pool. Species A reproduces both sexually and asexually, and Species B reproduce only asexually. The pool gradually becomes infested with disease-causing viruses. Which species are more likely to survive in the changing environment?
Species A only
dentify all possible products of meiosis in plant and animal life cycles.
Spores Gametes (sperm and eggs)
A triploid cell contains three sets of homologous chromosomes. Which of the following describes the chromosomes in a triploid cell where n = 6?
The cell has 18 total chromosomes in 6 sets.
What is the best evidence telling you whether this cell is diploid or haploid?
The cell is diploid because it contains two sets of chromosomes.
Which of the following statements describes the chromosomal makeup of each daughter cell after telophase of meiosis I?
The cells are haploid, and the chromosomes are each composed of two chromatids.
How do cells at the completion of meiosis compare with cells that are in prophase of meiosis I?
The cells have half the number of chromosomes and one-fourth the amount of DNA.
For what purpose(s) might a karyotype be prepared?
The first three answers are correct.
The somatic cells of a particular plant each contain a total of 46 chromosomes. How do the chromosomes of this plant differ from the chromosomes of humans, who also have a total of 46?
The genes on this plant's largest chromosome are significantly different than those on the largest human chromosome.
What must happen to a chromosome before a cell starts mitosis?
The single DNA molecule in the chromosome must be replicated.
This chromosome has two chromatids, joined at the centromere. What process led to the formation of the two chromatids?
The two chromatids were formed by duplication of a chromosome.
Which of the following statements best describes homologous chromosomes?
They carry information for the same traits.
Look at the cell in the figure. Based on this figure, which of the following statements is true?
This cell is diploid.
Cells from a diploid protist with n=1 are followed through mitosis and meiosis. The drawings in the figure below represent the chromosomes. Refer to the drawings and answer the following question. Which diagram represents anaphase II of meiosis?
V
Cells from a diploid protist with n=1 are followed through mitosis and meiosis. The drawings in the figure below represent the chromosomes. Refer to the drawings and answer the following question. Which diagram represents metaphase of mitosis?
VI
For the following question, match the key event of meiosis with the stages listed below. I. Prophase IV. Prophase IIII. Metaphase IVI. Metaphase IIIII. Anaphase IVII.Anaphase IIIV. Telophase IVIII.Telophase II Cohesins at centromeres of sister chromatids breakdown.
VII
For a species with a haploid number of 23 chromosomes, how many different combinations of maternal and paternal chromosomes are possible for the gametes based on the independent assortment of chromosomes during meiosis?
about 8 million
Which of the following events characterizes metaphase of mitosis?
alignment of the chromosomes at the equator
Which of the following processes will most likely produce a human zygote with 45 chromosomes?
an error during anaphase II while the sperm was produced
During which of the following phases of meiosis do homologous chromosomes separate?
anaphase I
During which of the following phases of meiosis do centromeres split and sister chromatids migrate to opposite poles of the cell?
anaphase II
If a plant biologist succeeds in generating a single plant with a particularly desirable flower, which of the following approaches would be the most efficient way to generate more plants with this trait?
clone the plant
During which of the following processes do sister chromatids separate from each other?
during both mitosis and meiosis II
Heritable variation is required for which of the following?
evolution
Many diploid organisms produce haploid gametes for reproduction. Which of the following best describes how the diploid number of chromosomes is restored in the offspring of these organisms?
fertilization combines chromosomes from each parent into resulting zygote
During which of the following processes does independent assortment of chromosomes occur?
in meiosis I only
Which of the following pairs of processes make the greatest contribution to genetic diversity between generations of a diploid insect?
independent assortment and random fertilization
In a human karyotype, chromosomes are arranged in 23 pairs. If one of the autosomal pairs is examined, which of the following characteristics will the two chromosomes of the pair have in common?
loci and staining pattern
Genetic variation occurs when chromosomes are shuffled in fertilization and what other process?
meiosis
Crossing over of chromosomes normally takes place during which of the following processes?
meiosis I
During which of the following processes do homologous pairs of chromosomes align adjacent to one another at the metaphase plate of a cell?
metaphase I of meiosis
Asexual reproduction occurs during which of the following processes?
mitosis
Asexual reproduction __________.
produces offspring genetically identical to the parent
Which of the following processes has just occurred when chiasmata can first be viewed under a microscope?
prophase I
Which of the following processes facilitates the fastest way for animal species to adapt to a changing environment?
sexual reproduction
Which of the following occurs during meiosis, but not during mitosis?
synapsis occurs
Which of the following processes occurs in meiosis but not in mitosis?
synapsis of chromosomes
Which of the following phrases defines the term genome?
the complete set of an organism's genes and other DNA sequences
Which of the following answers describes the phenomenon of crossing over in meiosis?
the exchange of homologous portions of nonsister chromatids
Independent assortment of chromosomes is a result of which of the following processes?
the random way each pair of homologous chromosomes lines up at the metaphase plate during meiosis I
Somatic cells of roundworms have four individual chromosomes per cell. How many chromosomes would you expect to find in an ovum from a roundworm?
two
In a typical animal, mitosis produces _________, while meiosis produces____________.
two diploid daughter cells, four haploid daughter cells
A (hypothetical) diploid organism has different genes that control wing length and wing color.A female of this species with short blue-colored wings has a chromosome pair with two short-wing alleles and a second chromosome pair with one blue-wing allele and one orange-wing allele. The eggs from this individual will have which of the following combinations of alleles?
1/2 of the eggs will have alleles for short blue-colored wings and 1/2 will have alleles for short orange-colored wings
The figure represents the nucleus of a diploid animal cell about to enter mitosis. How many different pairs of chromosomes are present in the diagram? The figure represents the nucleus of an animal cell about to enter mitosis. How many different chromosomes are present in the diagram?
4
What number and types of chromosomes are found in a human somatic cell?
44 autosomes and 2 sex chromosomes
