Exam 12: The Cell Cycle

Use the figure to answer the question below. The unlettered circle at the top of the figure shows a diploid nucleus with four chromosomes that have not yet replicated. There are two pairs of homologous chromosomes, one long and the other short. One haploid set is black, and the other is gray. The circles labeled A to E show various combinations of these chromosomes. What is the correct chromosomal condition at prometaphase of mitosis?

The M phase checkpoint ensures that all chromosomes are attached to the mitotic spindle. If this does not happen, cells would most likely be arrested in ________.

Early observations of a cultured cell line indicated that the cells did not exhibit either density-dependent inhibition or anchorage dependence. What do these observations suggest about this cell line?

Taxol is an anticancer drug extracted from the Pacific yew tree. In animal cells, Taxol prevents microtubule depolymerization. Thus, Taxol stops mitosis by interfering with which of the following structures or processes?

The mitotic spindle plays a critical role in which of the following processes?

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 per nucleus. In which stage of the cell cycle did the nucleus contain 6 picograms of DNA?

Which of the following molecules is a protein synthesized at specific times during the cell cycle that associates with a kinase to form a catalytically active complex?

What would you expect to happen if MPF (maturation-promoting factor)is introduced into immature frog oocytes that are arrested in G₂?

In a diploid cell with 5 chromosome pairs (2n = 10), how many centromeres will be found in a nucleus at G2 of the cell division cycle?

In the cells of some organisms, mitosis occurs without cytokinesis. This will result in

Use the figure to answer the question below. In the figure, at which of the numbered regions would you expect to find cells at metaphase?

Use the figure to answer the question below. If the cell whose nuclear material is shown in the figure continues toward completion of mitosis, which of the following events would occur next?

In a diploid cell with 5 chromosome pairs (2n = 10), how many sister chromatids will be found in a nucleus at prophase of mitosis?

Certain cell types normally have several nuclei per cell. How could such multinucleated cells be explained?

At which phase of the cell cycle do centrioles begin to move apart in animal cells?

G₁ is associated with which of the following cellular events?

The beginning of anaphase is indicated by which of the following processes?

Which of the following events occurs during interphase of the cell cycle?

Scientists isolate cells in various phases of the cell cycle. They isolate a group of cells that have 1 1/2 times more DNA than G₁ phase cells. What is the most likely part of the cell cycle from which these cells were isolated?

During which phase of mitosis do the chromatids become chromosomes?