chapter 12
A cell contains 40 chromatids at the beginning of mitosis. How many chromosomes will it contain at the completion of cytokinesis?
20
How many chromatids does a human somatic cell contain after interphase and just prior to mitosis?
92
Which of the following statements correctly describes the difference(s) between mitosis and binary fission?
Binary fission involves the replication and division of a single chromosome, whereas mitosis involves the division of multiple, replicated chromosomes
What is the difference between a benign tumor and a malignant tumor?
Cells of benign tumors do not metastasize; those of malignant tumors do
Which of the following events does not occur during interphase of the cell cycle?
Separation of the sister chromatids
Which event or events occur during anaphase?
identical chromatids move to opposite poles, the centrioles are at opposite poles, the centromeres drivide, and a spindle made of microtubles is present
Chromatids are __________
identical copies of each other if they are part of the same chromosome
Chromatids are __________.
identical copies of each other if they are part of the same chromosome
You would know a dividing cell was a plant cell rather than an animal cell if you saw that __________
it had formed a cell plate
You would know a dividing cell was a plant cell rather than an animal cell if you saw that __________.
it had formed a cell plate
The spread of cancer cells to other locations in the body is known as __________
metastasis
The spread of cancer cells to other locations in the body is known as __________.
metastasis
Which of the following structures is/are part of the mitotic spindle?
nonkinetochore microtubles, aster, centrosome, and kintetochore microtubes
Which of the following events occurs during prometaphase of mitosis?
the nuclear envelope fragments
During binary fission in a bacterium __________
the origins of replication move apart
During binary fission in a bacterium __________.
the origins of replication move apart
One event occurring during prophase is __________.
the beginning of the formation of a spindle apparatus
A cell biologist examined the DNA content of a cell from a fruit fly larva during the G1 phase and determined that it had 150 units of DNA. After measuring the DNA content of the same type of cell after the G2 phase, it was discovered that the cell had 300 units of DNA. How is this possible?
The DNA was replicated during the S phase of interphase, which occurs between the two G phases.
Which of the following statements describes a cell that undergoes mitosis but not cytokinesis?
The cell contains more than one nucleus
Which of the following events occurs during metaphase of mitosis?
The chromosomes align along the metaphase plate of the cell
Which of the following events does not occur during prophase of mitosis?
The mitotic spindle breaks down.
How does the process of mitosis differ between most eukaryotes and other eukaryotes such as diatoms and dinoflagellates?
The nuclear envelope fragments in most eukaryotes but remains intact in diatoms and dinoflagellates.
Which of the following events occurs during anaphase of mitosis?
The sister chromatids are pulled apart toward opposite sides of the cell.
Which of the following events occurs during telophase of mitosis?
Two distinct daughter nuclei form in the cell.
The region of a chromosome holding the two double strands of replicated DNA together is called __________
a centromere
The region of a chromosome holding the two double strands of replicated DNA together is called __________.
a centromere
The function of the mitotic cell cycle is to produce daughter cells that __________.
are genetically identical to the parent cell (assuming no mutation has occurred)
The complex of DNA and protein that makes up a eukaryotic chromosome is properly called __________.
chromatin
In animal cell mitosis, the cleavage furrow forms during which stage of the cell cycle?
cytokinesis
During interphase, the genetic material of a typical eukaryotic cell is __________.
dispersed in the nucleus as long strands of chromatin
Cytokinesis refers to __________
division of the cytoplasm
Observations of cancer cells in culture support the hypothesis that cancer cells __________
do not exhibit density-dependent inhibition
Observations of cancer cells in culture support the hypothesis that cancer cells __________.
do not exhibit density-dependent inhibition
One event occurring during prophase is __________
the beginning of the formation of a spindle apparatus
Checkpoints in the cell cycle control system __________.
regulate the cell cycle through a variety of stop and go signals
Which of the following phases of mitosis is essentially the opposite of prometaphase in terms of the nuclear envelope?
telophase
DNA replication occurs in __________.
the S phase of interphase in both somatic and reproductive cells