Exam 12: The Cell Cycle

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

The following information applies to the questions below. Several organisms,primarily protists,have what are called intermediate mitotic organization. -What is the most probable hypothesis about these intermediate forms of cell division?

A mutation results in a cell that no longer produces a normal protein kinase for the M phase checkpoint.Which of the following would likely be the immediate result of this mutation?

The following questions are based on the following figure. -In the figure above,mitosis is represented by which numbered part(s)of the cycle?

Which of the following triggers the cell's passage past the G₂ checkpoint into mitosis?

Use the following information to answer the questions below. A research team established similar lymphocyte cultures from a number of human donors,including healthy teenagers of both genders,patients already suffering from long-term bacterial infections,and elderly volunteers.They found that the increase in lymphocyte incorporation after pathogen introduction was slightly lower in some of the female teenagers and significantly lower in each of the elderly persons.They repeated the study with a larger number of samples but got the same results. -What might be among the research team's conclusions?

Use the following information to answer the questions below. A research team established similar lymphocyte cultures from a number of human donors,including healthy teenagers of both genders,patients already suffering from long-term bacterial infections,and elderly volunteers.They found that the increase in lymphocyte incorporation after pathogen introduction was slightly lower in some of the female teenagers and significantly lower in each of the elderly persons.They repeated the study with a larger number of samples but got the same results. -Which of the following investigations might be most productive to show what the data on the teenagers might indicate?

Use the data in the table below to answer the following questions. The data were obtained from a study of the length of time spent in each phase of the cell cycle by cells of three eukaryotic organisms designated beta,delta,and gamma. Minutes Spent in Cell Cycle Phases -The best conclusion concerning delta is that the cells

All cell cycle checkpoints are similar in which way?

Which of the following describe(s)cyclin-dependent kinase (Cdk)?

If there are 20 chromatids in a cell,how many centromeres are there?

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

You have the technology necessary to measure each of the following in a sample of animal cells: chlorophylls,organelle density,picograms of DNA,cell wall components,and enzymatic activity.Which would you expect to increase significantly from M to G₁?

Which of the following is (are)required for motor proteins to function in the movement of chromosomes toward the poles of the mitotic spindle?

Vinblastine is a standard chemotherapeutic drug used to treat cancer.Because it interferes with the assembly of microtubules,its effectiveness must be related to

For a chemotherapeutic drug to be useful for treating cancer cells,which of the following is most desirable?

The following questions are based on the following figure. -MPF reaches its threshold concentration at the end of this stage.

Use the following information to answer the questions below. A student is looking through his light microscope (~450 X)at a squashed and stained onion root tip.Some,but not all,of the cells have clearly visible chromosome strands. -When the cell has just completed telophase,which of the following does he see?

In eukaryotic cells,what are chromosomes are composed of?

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