Chapter 13 Meiosis & Sexual Lifestyles

Which of the following is an example of alternation of generations? A. A diploid plant (sporophyte) produces, by meiosis, a spore that gives rise to a multicellular, haploid pollen grain (gametophyte). B. A haploid mushroom produces gametes by mitosis, and the gametes undergo fertilization, which is immediately followed by meiosis. C. A diploid animal produces gametes by meiosis, and the gametes undergo fertilization to produce a diploid zygote. D. A grandparent and grandchild each have dark hair, but the parent has blond hair.

A. A diploid plant (sporophyte) produces, by meiosis, a spore that gives rise to a multicellular, haploid pollen grain (gametophyte).

If a horticulturist breeding gardenias succeeds in having a single plant with a particularly desirable set of traits, which of the following would be her most probable and efficient route to establishing a line of such plants? A. Clone the plant. B. Force the plant to self-pollinate to obtain an identical one. C. Backtrack through her previous experiments to obtain another plant with the same traits. D. Breed this plant with another plant with much weaker traits.

A. Clone the plant.

For what purpose(s) might a karyotype be prepared? Choose the best answer. A. For prenatal screening, to determine if a fetus has the correct number of chromosomes B. To determine whether a fetus is male or female C. To detect the possible presence of chromosomal abnormalities such as deletions, inversions, or translocations D. The first and second answers are correct. E. The first three answers are correct.

A. For prenatal screening, to determine if a fetus has the correct number of chromosomes B. To determine whether a fetus is male or female C. To detect the possible presence of chromosomal abnormalities such as deletions, inversions, or translocations E. The first three answers are correct ^

In a plant's sexual life cycle _____. A. Gametophytes produce gametes by mitosis B. Sporophytes produce gametes by meiosis C. Sporophytes produce gametes by mitosis D. Gametophytes produce gametes by meiosis

A. Gametophytes produce gametes by mitosis

Which of these is a karyotype? A. Organized images of a cells chromosomes B. The appearance of an organism C. A display of all of the cell types in an organism D. A display of a cells mitotic stages

A. Organized images of a cells chromosomes

Meiosis II is similar to mitosis in that A. Sister chromatids separate during anaphase. B. Homologous chromosomes synapse. C. DNA replicates before the division. D. the daughter cells are diploid. E. the chromosome number is reduced.

A. Sister chromatids separate during anaphase.

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

A. Synapsis occurs

At the end of _____ and cytokinesis, haploid cells contain chromosomes that each consist of two sister chromatids. A. Telophase I B. Telophase C. Telophase II D. Interphase E. Metaphase II

A. Telophase I

This chromosome has two chromatids, joined at the centromere. What process led to the formation of the two chromatids? A. The two chromatids were formed by duplication of a chromosome. B. The two chromatids were formed by synapsis and the formation of a synaptonemal complex. C. The two chromatids were formed by fertilization, bringing together maternal and paternal chromatids.

A. The two chromatids were formed by duplication of a chromosome.

Meiosis I produces _____ cells, each of which is _____. A. Two ... haploid B. Two... diploid C. Two... identical to the other D. Four ... diploid E. Four ... haploid

A. Two ... haploid

Mitosis results in the formation of how many cells; meiosis results in the formation of how many cells? A. Two diploid cells ... four haploid cells B. Two diploid cells ... two diploid cells C. Four haploid cells ... two diploid cells D. Four diploid cells ... four haploid cells E. Two diploid cells ... two haploid cells

A. Two diploid cells ... four haploid cells

Quaking aspen can send out underground stems for asexual reproduction. Sexual reproduction is not as common, but when it does happen, the haploid gametes have 19 chromosomes. How many chromosomes are in the cells of the underground stems? A. 10 B. 38 C. 9 D. 19

B. 38

Homologous chromosomes migrate to opposite poles during _____. A. Telophase II and cytokinesis B. Anaphase I C. Metaphase II D. Prophase II E. Metaphase I

B. Anaphase I

Two sister chromatids are joined at the centromere prior to meiosis. Which statement is correct? A. The cell that contains these sister chromatids must be haploid. B. Barring mutation, the two sister chromatids must be identical. C. These chromatids make up a diploid chromosome.

B. Barring mutation, the two sister chromatids must be identical.

Look at the cell in the figure. Based on this figure, which of the following statements is true? A. It is impossible to tell whether the cell is haploid or diploid. B. This cell is diploid. C. This cell is haploid.

B. This cell is diploid

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? A. DNA content is halved only in meiosis II. Ploidy level changes from diploid to haploid in meiosis I, and remains haploid in meiosis II. B. 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. C. DNA content is halved in both meiosis I and meiosis II. Ploidy level changes from diploid to haploid only in meiosis II. D. DNA content is halved only in meiosis I. Ploidy level changes from diploid to haploid only in meiosis II. E. DNA content is halved only in meiosis I. Ploidy level changes from diploid to haploid in meiosis I, and remains haploid in meiosis II.

B. 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.

Meiosis II typically produces _____ cells, each of which is _____. A. Two ... haploid B. Four ... haploid C. Four ... diploid D. Four ... identical to the other E. Two... diploid

B. Four ... haploid

Identify all possible products of meiosis in plant and animal life cycles. Select all that apply. A. Multicellular adult organisms B. Gametes (sperm and eggs) C. Spores

B. Gametes (sperm and eggs) C. Spores

Asexual reproduction _____. A. Leads to a loss of genetic material B. Produces offspring genetically identical to the parent C. Is limited to plants D. Requires both meiosis and mitosis E. Is limited to single-cell organisms

B. Produces offspring genetically identical to the parent

Asexual reproduction occurs during _____. A. Meiosis B. Chromosome exchange between organisms of different species C. Mitosis D. Fertilization

C. Mitosis

Synapsis occurs during _____. A. Prophase II B. Metaphase II C. Prophase I D. Telophase I and cytogenesis E. Anaphase II

C. Prophase I

In alternation of generations, what is the diploid stage of a plant that follows fertilization called? A. Chiasmata B. Karyotype C. Sporophyte D. Gametophyte E. Spore

C. Sporophyte

What is the best evidence telling you whether this cell is diploid or haploid? A. The cell is haploid because the chromosomes are not found in pairs. B. The cell is diploid because each chromosome consists of two chromatids. C. The cell is diploid because it contains two sets of chromosomes.

C. The cell is diploid because it contains two sets of chromosomes.

What is crossing over? A. The movement of genetic material from one chromosome to a nonhomologous chromosome B. Also referred to as the "independent assortment of chromosomes" C. The exchange of homologous portions of nonsister chromatids D. Making an RNA copy of a DNA strand E. Direct consequence of the separation of sister chromatids

C. The exchange of homologous portions of nonsister chromatids

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 A. 0.25x. B. x. C. 4x. D. 2x. E. 0.5x.

D. 2x.

What number and types of chromosomes are found in a human somatic cell? A. 45 autosomes and 1 sex chromosome B. n chromosomes C. 21 autosomes and 2 sex chromosomes D. 44 autosomes and 2 sex chromosomes E. 22 autosomes and 1 sex chromosome

D. 44 autosomes and 2 sex chromosomes

During _____ sister chromatids separate. A. Prophase I B. Prophase II C. Interphase D. Anaphase II E. Metaphase I

D. Anaphase II

Homologous chromosomes _____. A. Align on the metaphase plate in meiosis II B. Carry the same alleles C. Are identical D. Carry information for the same traits

D. Carry information for the same traits

Homologous chromosomes move toward opposite poles of a dividing cell during A. Mitosis. B. Fertilization. C. Binary fission. D. Meiosis I. E. Meiosis II.

D. Meiosis I.

During _____ chromosomes align single file along the equator of a haploid cell. A. Prophase I B. Metaphase I C. Anaphase I D. Metaphase II E. Telophase I and cytokinesis

D. Metaphase II

Which of the following defines a genome? A. The complete set of a species' polypeptides B. A karyotype C. The complete set of an organism's polypeptides D. The complete set of an organism's genes and other DNA sequences

D. The complete set of an organism's genes and other DNA sequences

A human cell containing 22 autosomes and a Y chromosome is A. A somatic cell of a male. B. A zygote. C. An egg. D. A somatic cell of a female. E. A sperm.

E. A sperm

How are sister chromatids and homologous chromosomes different from each other? A. They are not different. Homologous chromosomes and sister chromatids are both identical copies of each other. B. Sister chromatids are only formed during mitosis. Homologous chromosomes are formed during meiosis. C. Homologous chromosomes are identical copies of each other. One sister chromatid comes from the father, and one comes from the mother. D. Homologous chromosomes are closely associated with each other in both mitosis and meiosis. Sister chromatids are only associated with each other during mitosis. E. 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.

E. 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

During _____ a spindle forms in a haploid cell. A. Prophase I B. Anaphase II C. Metaphase II D. Telophase I and cytokinesis E. Prophase II

E. Prophase II

At the end of _____ and cytokinesis there are four haploid cells. A. Prophase II B. Prophase I C. Interphase D. Anaphase I E. Telophase II

E. Telophase II