C. the mitotic spindles in prokaryotic cells are composed of microtubules
A cell containing 92 chromatids at metaphase of mitosis would, at its completion, produce two nuclei containing how many chromosomes?
If the cell whose nuclear material is shown in Figure 12.2 continues toward completion of mitosis, which of the following events would occur next?
B. formation of telophase nuclei
The S phase was measured by:
B. determining the start and stop of increased DNA in the cells
Cytokinesis usually, but not always, follows mitosis. If a cell completed mitosis but not cytokinesis, what would be the result?
B. a cell with two nuclei
Taxol is an anticancer drug extracted from the Pacific yew tree. In animal cells, taxol disrupts microtubule formation by binding to microtubules and accelerating their assembly from the protein precursor, tubulin. Surprisingly, this stops mitosis. Specifically, taxol must affect:
B. the fibers of the mitotic spindle
Cells that are in a nondividing state are in which phase?
Measurements of the amount of DNA per nucleus were taken on a larger number of cells from a growing fungus. The measured DNA levels ranged from 3 to 6 picograms per nucleus. In which stage of the cell cycle was the nucleus with 6 picograms of DNA?
The MPF protein complex turns itself off by
E. activating an enzyme that destroys cyclin
Proteins that are involved in the regulation of the cell cycle and that show fluctuations in concentration during the cell cycle are called