Exam 12: The Cell Cycle

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

Nucleotides can be radiolabeled before they are incorporated into newly synthesized DNA and, therefore, can be assayed to track their incorporation. In a set of experiments, a student-faculty research team used labeled T nucleotides and introduced these into a culture of dividing human cells at specific times. Which of the following questions might be answered by using the method described?

Nucleotides can be radiolabeled before they are incorporated into newly forming DNA and, therefore, can be assayed to track their incorporation. In a set of experiments, a student-faculty research team used labeled T nucleotides to study the incorporation of labeled nucleotides into a culture of lymphocytes. They found that the lymphocytes incorporated the labeled nucleotide at a significantly higher level after a pathogen was introduced into the culture. What might they conclude from this observation?

Density-dependent inhibition is explained by which of the following processes?

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?

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

Which of the following properties is associated with a cyclin-dependent kinase (Cdk)?

Use the figure to answer the question below. In the figure, which number represents DNA synthesis?

Exposure of zebrafish nuclei to cytosol isolated from eggs at metaphase of mitosis resulted in phosphorylation of NEP55 and L68 proteins by cyclin-dependent kinase 2. NEP55 is a protein of the inner nuclear membrane, and L68 is a protein of the nuclear lamina. What is the most likely role of phosphorylation of these proteins in the process of mitosis?

Use the figure to answer the question below. In the figure, MPF reaches its highest concentration during this stage.

What is the name of the microtubule-organizing center found in animal cells as an identifiable structure present during all phases of the cell cycle?

Metaphase is characterized by ________.

If a cell at metaphase of mitosis contains 20 sister chromatids, how many chromosomes will be present in a G₁ cell?

The drug cytochalasin B blocks the function of actin. Which of the following aspects of the animal cell cycle would be most disrupted by cytochalasin B?

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

Which of the following does not occur during mitosis?

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?

One difference between cancer cells and normal cells is that cancer cells

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 ________.

Starting with a fertilized egg (zygote), a series of six cell divisions would produce an early embryo with how many cells?