Exam 11: The Cell Cycle

The microtubule-organizing center found in animal cells is an identifiable structure present during all phases of the cell cycle.Specifically,it is known as which of the following?

FtsZ is a bacterial cytoskeletal protein that forms a contractile ring involved in bacterial cytokinesis.Its function is analogous to _____.

What happens when MPF (mitosis-promoting factor)is introduced into immature frog oocytes that are arrested in G₂?

What is the final result of mitosis?

In eukaryotic cells,chromosomes are composed of _____.

Figure 11.1 -Based on structures present in Figure 11.1,this cell is in which substage of interphase?

Which cytoskeletal proteins are important constituents of the contractile structures that form the cleavage furrows involved in animal cell cytokinesis?

If a cell has accumulated DNA damage,it is unlikely to _____.

The first gap in the cell cycle (G₁)corresponds to _____.

Which of the following statements about cancer is not true?

Following the attachment of spindle microtubules to kinetochores,chromosomes are moved around by _____.

A parent cell divides to form two genetically identical daughter cells in the process of mitosis.For mitosis to take place _____.

Myosin is a motor protein involved in animal cell cytokinesis.It binds to ATP or ADP,causing the myosin to move with respect to actin.What is the effect of the interaction between myosin and actin?

Scientists isolate cells in various phases of the cell cycle.They find a group of cells that have 1½ times more DNA than do G₁ phase cells.The cells of this group are _____.

The M-phase checkpoint is designed to make sure all chromosomes are attached to the mitotic spindle.If this fails to happen,in which stage of mitosis would the cells be most likely to arrest?

Mitosis is the process of chromosome separation.Cytoplasm is divided between the two daughter cells in a process known as _____.

Exposure of zebrafish nuclei to meiotic cytosol 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?

In the process of chromosome separation,how do microtubules maintain contact with the kinetochores and shorten at the same time?

Metaphase occurs prior to the splitting of centromeres.It is characterized by _____.

For cells to divide more rapidly,increased production would likely be required of each of the following proteins except _____.