Mastering Bio Mitosis and Meiosis

A cell preparing to undergo meiosis duplicates its chromosomes during A. interphase. B. prophase I. C. meiosis II. D. anaphase I. E. metaphase I.

A. Interphase

The chromosomes line up in the center of the cell during which phase of mitosis? A. Metaphase B. Telophase C. Prophase D. Interphase E. Anaphase

A. Metaphase

The chromosomes arrive at the poles and nuclear envelopes form during which phase of mitosis? A. Metaphase B. Telophase C. Prophase D. Interphase E. Anaphase

B. Telophase

During meiosis, segments of nonsister chromatids can trade places. This recombination of maternal and paternal genetic material is a key feature of meiosis. During what phase of meiosis does recombination occur? A. telophase I. B. anaphase I. C. prophase I. D. Metaphase I. E. meiosis II.

C. prophase I

At the end of the mitotic (M) phase, the cytoplasm divides in a process called? A. telophase B. meiosis C. condensation D. cytokinesis E. replication

D. cytokinesis

During prophase I of meiosis, A. homologous chromosomes stick together in pairs. B. there are two daughter cells, each with 23 chromosomes. C. chromosome pairs are positioned in the middle of the cell. D. there are four haploid daughter cells. E. the homologous chromosomes separate and move towards opposite poles.

A. Homologous chromosomes stick together in pairs

Which of the following statements correctly describes the timing of DNA synthesis? A. DNA is synthesized only during mitosis. B. DNA is synthesized in the S phase of interphase. C. DNA is synthesized continuously throughout the cell cycle D. DNA is synthesized in G2 of interphase immediately preceding mitosis.

B. DNA is synthesized in the S phase of interphase.

You suspect that a serious developmental disorder is due to a chromosome abnormality and prepare a karyotype from an affected individual. In analyzing the karyotype, how could you distinguish trisomy from a chromosome structural defect such as a duplication? A. The chromosome number in trisomy would be normal; in a duplication, there would be one more chromosome. B. In trisomy there would be one extra chromosome; in a duplication, the number of chromosomes would be normal, but one chromosome would have two copies of a portion of the chromosome. C. The chromosome number in both cases would be normal, but in trisomy there would be three chromatids on one chromosome and in a duplication there would be two chromatids on one chromosome. D. In both cases there would be an extra chromosome, but in trisomy there would be three chromatids on one chromosome and in a duplication there would be two chromatids on one chromosome.

B. In trisomy there would be one extra chromosome; in a duplication, the number of chromosomes would be normal, but one chromosome would have two copies of a portion of the chromosome.

A cell replicates its entire chromosomal DNA only __________. A. when it makes protein B. before it is about to divide C. to repair damage caused by mutation D. when the cell needs RNA

B. before it is about to divide

The function of meiosis is to make __________. A. exact copies of the parent cell B. four cells with a haploid number of chromosomes C. one cell with twice the number of chromosomes as the parent cell D. four cells with the same chromosome number as the parent cell

B. four cells with a haploid number of chromosomes

The centrosomes move away from each other and the nuclear envelope breaks up during which case of mitosis? A. Metaphase B. Telophase C. Prophase D. Interphase E. Anaphase

C. Prophase

Chromatids are _____. A. held together by the centrioles B. not present in the Y sex chromosome, but present in the X sex chromosome C. identical copies of each other if they are part of the same chromosome D. found only in aberrant chromosomes

C. identical copies of each other if they are part of the same chromosome

What must happen before a cell can begin mitosis? A. The sister chromatids must be separated. B. The nucleus must divide in two. C. The nuclear envelope must break up. D. The chromosomes must be duplicated. E. A mitotic spindle must form.

D. The chromosomes must be duplicated

The correct order of events during meiosis is A. prophase I, anaphase I, metaphase I, telophase I, meiosis II, cytokinesis. B. metaphase I, prophase I, anaphase I, telophase I, cytokinesis, meiosis II. C. metaphase I, prophase I, telophase I, anaphase I, cytokinesis, meiosis II. D. prophase I, metaphase I, anaphase I, telophase I, cytokinesis, meiosis II. E. prophase I, anaphase I, telophase I, metaphase I, meiosis II.

D. prophase I, metaphase I, anaphase I, telophase I, cytokinesis, meiosis II

The sister chromatids separate and begin moving toward opposite poles of the cell during which phase of mitosis? A. Metaphase B. Telophase C. Prophase D. Interphase E. Anaphase

E. Anaphase

Meiosis starts with a single diploid cell and produces A. eight haploid cells. B. two diploid cells. C. two haploid cells. D. four diploid cells. E. four haploid cells.

E. four haploid cells