16.
in plant cells, cytokinesis is completed by the formation of a(n)

cell plate.

equatorial plate.

membrane furrow.

spindle.
17.
in which of the following cases would asexual reproduction be most advantageous for an organism?

living where there are many available partners

when the need for adaptation is great

when new organisms are moving into and out of the population

living in a stable environment with little variation
18.
if a cell is exposed to a chemical that inhibits the production of spindle fibers as the cell is preparing for mitosis, what would most likely happen?

the cell would continue with mitotic division.

the cell would break open.

the cell would not divide.

the cell would undergo meiotic division.
19.
which of the following statements lists the steps that occur in the cell cycle, in chronological order?

centrioles move to opposite ends of the cell; cell passes through g1 checkpoint

sister chromatids are pulled apart to opposite ends of the cell; spindle fibers begin to appear

sister chromatids align in the middle; cytoplasm pinches in to separate daughter cells

nuclear membrane disappears; chromatin condenses
20.
devil facial tumor disease (dftd) is a disease that is decimating the population of tasmanian devils. the disease passes from one animal to another through bites and is caused by parasites. the parasites cause cancerous tumors that spread throughout an infected animal's body and kill it. what is the best description of dftd?

a non-infectious, cell-cycle disease

a non-infectious, chronic disease

an infectious, chronic disease

an infectious, cell-cycle disease
21.
the disruption of which cell function leads to gene mutations that result in cancer?

rna translation

rna transcription

protein synthesis

dna replication
22.
during the time of normal cell activity, dna exists in a loose, spaghetti-like form called

centromere

chromosomes

chromatin

histone
23.
the table below identifies three classes of genes that affect the cell cycle.

gene type gene activity
proto-oncogenes regulate progress though the normal cell
cycle
oncogenes cause uncontrolled cell cycle progression
tumor suppressor genes restrict cell cycle progression
which scenario transforms normal cells into cancer cells?

oncogenes become proto-oncogenes.

tumor suppressor genes become oncogenes.

proto-oncogenes become oncogenes.

tumor suppressor genes become pro-oncogenes.