Gen Bio Chapter 12 (cell cycle ) mitosis
The DNA was replicated during the S phase of interphase, which occurs between the two G phases.
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?
20
A cell contains 40 chromatids at the beginning of mitosis. How many chromosomes will it contain at the completion of cytokinesis?
asexual reproduction and mitosis
A clone is the product of ____
46
A human stem contains 46 chromosomes in its nucleus. How many replicated chromosomes go to each spindle pole during mitosis?
fungi
A life cycle in which the only multicellular form is haploid is most typical of
homologous chromosomes
A pair of genetic structures carrying genes that control the same inherited characters are called
genetic diversity
Allelic variation is an important source of __________ in a population.
two; identical; four; distinct
At the end of mitosis, __________ daughter cells that are genetically __________ are formed, while at the end of meiosis, __________ daughter cells that are genetically __________ are formed.
Line up at the Equatorial plate (metaphase plate )
At the milestone that defines metaphase , the chromosomes ______.
Prophase
At which phase are centrioles beginning to move apart in animal cells ?
binary fission
Bacteria divide by a process called ____.
G1 phase
Cell growth
is an example of an animal that has not reproduced sexually in 40 million years
Characteristic of the bdelloid rotifer is that it _
identical copies of each other if they are part of the same chromosome
Chromatids are
mitosis
Cytokinesis is not apart of
S phase (synthesis)
DNA replication
s Phase
DNA replication takes place in which phase of the cell cycle?
even though he never read any of Gregor Mendel's work
Darwin realized the importance of heritable variation to evolution
the origins of replication move apart
During binary fission in a bacterium
dispersed in the nucleus as long strands of chromatin
During interphase, the genetic material of a typical eukaryotic cell is
92
How many chromatids does a human somatic cell contain after interphase and just prior to mitosis?
tens of thousands
How many genes are present in the human genome?
16
Ignoring crossover, how many kinds of gametes can be produced by an organism with a diploid number of 8?
nonsister chromatids; homologous pairs; chiasmata
In meiosis, __________ of __________ cross over and form __________.
cells will spend most of their life in (90 %)
Interphase
G1 phase, S phase, G2 phase
Interphase includes what 3 phases?
centromeres
Kinetochores are protein complexes associated with
do not exhibit density-dependent inhibition
Observations of cancer cells in culture support the hypothesis that cancer cells
During meiosis II, cohesion holds sister chromatids together along their lengths as the second meiotic spindle forms.
Regarding the role of cohesin protein in maintaining cohesion between sister chromatids, which of the following statements is false?
are products of the S phase of the cell cycle and are two copies of one chromosome
Sister chromatids differ from nonsister chromatids in that sister chromatids __________.
are all of the cells of the body except for the gametes and their precursors
Somatic cells in animals differ from gametes in that somatic cells __________.
two; diploid
Somatic cells in humans contain __________ set(s) of chromosomes and are therefore termed __________.
contain two sets of each of the 23 chromosome types
Somatic cells in humans differs from gametes in that human somatic cells ___
Chromatin
The complex of DNA and protein that makes up a eukaryotic chromosome is properly called
44
The egg (ovum) of a rabbit contains 22 chromosomes. How many chromosomes are in the somatic (body) cells of a rabbit?
are genetically identical to the parent cell (assuming no mutation has occurred)
The function of the mitotic cell cycle is to produce daughter cells that
alternation of generations; haploid gametophyte; diploid sporophyte
The life cycle called __________ in plants has two multicellular stages: the __________ and the __________.
it provides a method to increase genetic variation
The major contribution of sex to evolution is that __________.
What is a locus?
The precise location of a gene on a chromosome.
meiosis; two consecutive cell divisions
The process called __________ reduces the chromosome number by __________.
a centromere
The region of a chromosome holding the two double strands of replicated DNA together is called
metastasis
The spread of cancer cells to other locations in the body is known as
prophase I; synaptonemal complex
The zipper-like complex that forms in meiosis occurs during __________ and is called the __________.
homologous chromosomes
They have genes for the same traits at the same loci.
a plant cell in the process of cytokinesis
Through a microscope , you can see a cell plate beginning to develop across the middle of a cell and nuclei forming on either side of the cell plate . This cell plate is most likely _____.
Part of a chromosome turned around.
Unless the chromosomes were stained to show band patterns, a karyotype would be least likely to show which of the following?
Cells of benign tumors do not metastasize; those of malignant tumors do.
What is the difference between a benign tumor and a malignant tumor?
Four haploid cells
What is the result when a diploid cell undergoes meiosis?
Multicellular haploid
Which life cycle stage is found in plants but not animals?
replication of the DNA
Which of the following does not occur during mitosis ?
The mitotic spindle breaks down.
Which of the following events does not occur during prophase of mitosis?
The nuclear envelope fragments.
Which of the following events occurs during prometaphase of mitosis?
Two distinct daughter nuclei form in the cell.
Which of the following events occurs during telophase of mitosis?
Multiplication of body cells
Which of the following is a function of mitosis in humans?
Homologous chromosomes separate.
Which of the following occurs in meiosis, but not mitosis?
telophase
Which of the following phases of mitosis is essentially the opposite of prometaphase in terms of the nuclear envelope
Mitosis
Which of the following phases of the cell cycle is not apart of interphase ?
Binary fission involves the replication and division of a single chromosome, whereas mitosis involves the division of multiple, replicated chromosomes.
Which of the following statements correctly describes the difference(s) between mitosis and binary fission?
The cell contains more than one nucleus.
Which of the following statements describes a cell that undergoes mitosis but not cytokinesis?
Nonkinetochore microtubules Kinetochore microtubules Centrosome The aster
Which of the following structures is/are part of the mitotic spindle?
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
The centromere
_____ is a region in which Chromatids remain attaches to one another until anaphase
Clones; asexual reproduction
__________ are a group of genetically identical individuals produced by a process called __________
DNA in a cell constitutes
cell genomes are all the __
Cytokinesis is
cytoplasmic division
centrioles
made up of microtubules involved in the movement of chromosomes in mitosis/miosis
G2 phase
more cell growth and prepare for mitosis
Somatic cells
non reproductive and have 2 sets of chromosomes
Mitosis is
nuclear division
phases of mitosis in order
prophase prometaphase metaphase anaphase telophase
Centrosome
region that holds 2 centrioles
anaphase
sister chromatids separate in
The products of mitosis are
two genetically identical nuclei
each duplicated chromosomes has __
two sister chromatids with a centromere
a groove in the plasma membrane between daughter nuclei
what is a cleavage furrow?
