chp 12 practice quiz
a cell biologist carefully measured the quantity of dna in grasshopper cells growing in cell culture. cells examined during the g2 phase of the cell cycle contained 200 units of dna. what would the amount of dna at g1 of the cell cycle in one of the grasshopper daughter cells?
100
which of the following processes does not occur in dividing bacteria?
(mitosis) binary fission seperation of the origins of replication relpication of dna inward growth of the plasma membrane
following cytokinesis in an animal cell, how many centrioles does each new daughter cell possess
2
how many maternal chromosomes are present in a somatic human cell not engaged in cell division
23
assume that you are dealing with a species in which the number of chromosomes in each somatic cell is 14. how many chromatids are present in the early telophase of mitiosis?
28
if a cell contains 60 chromatids at the start of mitosis, how many chromosomes will be found in each daughter cell at the completion of the cell cycle?
30
if a somatic human cell is just about to divide it has how many chromatids?
92 chromatids
down syndrome is characterized by cells having 3 copies of chromosome 21. as a cell in an individual with down syndrome prepares to enter mitosis, how many chromatids would be present?
94 chromatids
a biochemist measured the amount of dna in cells growing in the laboratory and found that the quantity of dna in cells doubled
between g1 and g2 phases
during interphase the genetic material of a typical eukaryotic cell
dispersed in the nucleus as long strands of chromatin
which of the following is involved in the binary fission of bacteria
distribution of a copy of the single parental chromosome to each daughter cell
cytokinesis refers to
division of the cytoplasm
when a cell in s phase is fused with a cell in g1
dna synthesis begins immediately in the original g1 nucleus
observations of cancer cells in culture support the hypothesis that cancer cells
do not exhibit density-dependent inhibition
the function of the mitotic cell cycle is to produce daughter cells that are
genetically identical to the parent cell (assuming no mutation has occured)
tissue culture experiments with pdgf demonstrate that without this substance
cells fail to divide
what is the difference between a benign tumor and a malignant tumor
cells of benign tumors do not metastasize those of malignant tumors do
the region of a chromosome holding the two double strands of replicated dna together
centromere
these are indentical copies of each if they are part of the same chromosome
chromatids
the complex dna and protein that makes up a eukaryotic chromosome is called
chromatin
what does occur in mitosis?
condensation of chromatin (prophase) the movement of chromosomes to opposite poles (metaphase) seperation of chromatids (anaphase) alignment of chromosomes along the cells equator (metaphase)
in animal cell mitosis, the cleavage furrow forms during which stage of the cell cycle?
cytokinesis
what does not occur in mitosis?
replication of chromosomes occurs in the s phase of interphase
the centromere is a region in which
sister chromatids are attached to one another in prophase
the truth about sister chromatids
sister chromatids are created when dna is replicated sister chromatids form in the s-phase stage of the cell cycle sister chromatids are attached to one another at the centromere sister chromatids are separated during mitosis
which of following phases of mitosis is essentially the opposite of prometaphase in terms of the nuclear envelope
telophase
during binary fission in a bacterium
the origins of replication move apart
dna replication occurs in
the s phase of interphase in both somatic and reproductive cells
what events occur in anaphase
a spindle made of microtubules is present the centrioles are opposite poles identical chromatids move to opposite poles the centromeres divide
during what stage of the cell cycle do sister chromatids separate?
anaphase
the phase of mitosis during which the chromosomes move towards separate poles of the cell is
anaphase
during what phase in the cell cycle would you find the most dna per cell?
end of s
you would know a dividing cell was a plant cell rather than an animal cell by what
if you saw that it had formed a cell plate
at which stage of mitosis are chromosomes lined up in one plane in preparation for their separation to opposite poles of the cell?
metaphase
you would be unlikely to see which of the following human cells dividing?
nerve cell
the nuclear envelope disappears in what phase
prometaphase
in a human skin that is going through the cell cycle, when do the centrosomes seperate?
prophase
in telophase of mitosis spindle breaks down and the chromatin uncoils. this essentially the opposite of what happens in
prophase
the beginning of the formation of the spindle apparatus occurs in
prophase