General Biology II - Exam 2

During _____ sister chromatids separate. A.) anaphase II B.) prophase I C.) metaphase I D.) prophase II E.) interphase

A.) anaphase II

During _____ a spindle forms in a haploid cell. A.) prophase II B.) anaphase II C.) prophase I D.) metaphase II E.) telophase I and cytokinesis

A.) prophase II

At the end of _____ and cytokinesis, haploid cells contain chromosomes that each consist of two sister chromatids. A.) telophase I B.) telophase II C.) interphase D.) metaphase II E.) telophase

A.) telophase I

Which stage of mitosis is characterized by the disintegration of mitotic spindles and the formation of two new nuclear membranes? A.) Prophase B.) Telophase C.) Anaphase D.) Metaphase

B.) Telophase

In human and many other eukaryotic species' cells, the nuclear membrane has to disappear in order for what to take place? A.) disassembly of the nucleolus B.) attachment of mitotic spindle to kinetochores C.) cytokinesis D.) splitting of the centrosomes

B.) attachment of mitotic spindle to kinetochores

Cytokinesis often, but not always, accompanies _____. A.) interphase B.) telophase C.) metaphase D.) anaphase E.) prometaphase

B.) telophase

During which substage of mitosis do sister chromatids break apart and start moving to opposite poles of the cell? A.) Prophase B.) Telophase C.) Anaphase D.) Metaphase

C.) Anaphase

Nerve cells lose their ability to undergo mitosis. Instead, they are permanently stuck in ________. A.) S of interphase. B.) meiosis. C.) G0. D.) G2.

C.) G0.

Which event does not take place before the start of mitosis? A.) DNA is replicated. B.) Organelles proliferate. C.) The nuclear envelope disintegrates. D.) The parent cell grows.

C.) The nuclear envelope disintegrates.

Which statement about the daughter cells of mitosis is correct? A.) They differ genetically from one another and from the parent cell. B.) Only one of the two daughter cells is genetically identical to the parent cell. C.) They are genetically identical to one another and to the parent cell. D.) They are genetically identical to one another but are different from the parent cell.

C.) They are genetically identical to one another and to the parent cell.

Homologous chromosomes migrate to opposite poles during _____. A.) metaphase II B.) prophase II C.) anaphase I D.) telophase II and cytokinesis E.) metaphase I

C.) anaphase I

What are homologous chromosomes? A.) the products of crossing over, which contain a combination of segments from maternal chromosomes and segments from paternal chromosomes B.) the two "threads" in a replicated chromosome (they are identical copies) C.) chromosomes that are similar in their size, shape, and gene content D.) similar chromosomes that are found in different individuals of the same species

C.) chromosomes that are similar in their size, shape, and gene content

Chromosomes become visible during _____. A.) metaphase B.) prometaphase C.) prophase D.) anaphase E.) interphase

C.) prophase

Once researchers understood that chromosomes are moved by the spindle microtubules, the next question they wanted to answer is how the microtubules function to bring about this process. They used fluorescent labels to make the chromosomes and the microtubular structures fluoresce. When anaphase began (centromeres split), they photobleached a section of microtubules. As chromosomes moved toward the poles of the daughter cells, the photobleached sections of the microtubules remained stationary. This result suggests that ________. A.) the microtubules are of constant length; centrosomes move farther apart to separate chromosomes. B.) the microtubules overlap, and slide with respect to each other, effectively shortening the microtubules without depolymerizing the actual fiber. C.) the microtubules elongate and shorten at their kinetochore end. D.) the microtubules elongate and shorten at the centrosome end.

C.) the microtubules elongate and shorten at their kinetochore end.

To which part of the centromere do mitotic spindle fibers attach during prometaphase? A.) Chromosome B.) Centriole C.) Microtubule D.) Kinetochore

D.) Kinetochore

During which stage of mitosis are chromosomes lined up in the center of the cell? A.) Prophase B.) Anaphase C.) Telophase D.) Metaphase

D.) Metaphase

Which term describes two recently replicated DNA strands that are joined together just before cell division? A.) Centriole B.) Centrosome C.) Centromere D.) Sister chromatids

D.) Sister chromatids

What evidence suggests that during anaphase, spindle fibers shorten at the kinetochore and not at the base of the mitotic spindle? A.) When fluorescing microtubules are bleached in the middle, the bleached segment moves toward the base of the mitotic spindle as the fibers shorten near the microtubule organizing center. B.) Motor proteins are located at the kinetochore. C.) Motor proteins are located at the kinetochore and at the base of the mitotic spindle. D.) When fluorescing microtubules are bleached in the middle, the bleached segment stays stationary as the fibers shorten near the kinetochore.

D.) When fluorescing microtubules are bleached in the middle, the bleached segment stays stationary as the fibers shorten near the kinetochore.

Metaphase occurs prior to the splitting of centromeres. It is characterized by ________. A.) duplication of centrioles. B.) disassembly of the nuclear envelope. C.) cytokinesis. D.) aligning of chromosomes on the equator.

D.) aligning of chromosomes on the equator.

Spindle fibers attach to kinetochores during _____. A.) anaphase B.) interphase C.) metaphase D.) prometaphase E.) telophase

D.) prometaphase

Synapsis occurs during _____. A.) anaphase II B.) metaphase II C.) prophase II D.) prophase I E.) telophase I and cytogenesis

D.) prophase I

At the end of _____ and cytokinesis there are four haploid cells. A.) prophase I B.) anaphase I C.) prophase II D.) telophase II E.) interphase

D.) telophase II

Centromeres divide and sister chromosomes become full-fledged chromosomes during _____. A.) metaphase B.) interphase C.) prometaphase D.) telophase E.) anaphase

E.) anaphase

Nucleoli are present during _____. A.) anaphase B.) prophase C.) prometaphase D.) metaphase E.) interphase

E.) interphase

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

E.) two ... haploid

True or false? Mitosis takes place during M phase, which is the longest phase of the cell cycle.

False