End Ch.9 Questions
sister chromatid
1 of 2 genetically identical chromosome units that are the result of DNA replication.
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caspase
A "killer enzyme" that plays a role in apoptosis, or programmed cell death
signal
A behavior that causes change in another's behavior.
cyclin
A cellular protein that occurs in a cyclically fluctuating concentration and that plays an important role in regulating the cell cycle.
nucleoid
A dense region of DNA in a prokaryotic cell.
cell plate
A double membrane across the midline of a dividing plant cell, between which the new cell wall forms during cytokinesis.
binary fission
A form of asexual reproduction in single-celled organisms by which one cell divides into two cells of the same size
tumor suppressor gene
A gene whose protein products inhibit cell division, thereby preventing uncontrolled cell growth (cancer).
inhibit the cell cycle
A mutation in a tumor suppressor gene may...
aster
A radial array of short microtubules that extends from each centrosome toward the plasma membrane in an animal cell undergoing mitosis.
centrosome
A structure in animal cells containing centrioles from which the spindle fibers develop.
kinetocore
A structure of proteins attached to the centromere that links each sister chromatid to the mitotic spindle.
Since histones are only needed during S stage, one would expect to see high amounts made then, and no synthesis at all during G1 and G2.
After DNA is duplicated in eukaryotes, it must be bound to histones. This requires the synthesis of hundreds of millions of new protein molecules. With reference to fig.9.1, when in the cell cycle would histones be made?
telophase
After the chromosome seperates, the cell seals off, Final Phase of Mitosis.
mitotic spindle
An assemblage of microtubules and associated proteins that is involved in the movements of chromosomes during mitosis.
centromere
Area where the chromatids of a chromosome are attached
duplicated chromosomes
At the metaphase plate during metaphse of mitosis, there are...
prophase
Chromosomes become visable, nuclear envelop dissolves, spindle forms
chromatin
Clusters of DNA, RNA, and proteins in the nucleus of a cell
centromere
Constriction where sister chromatids of a chromosome are held together. point of attachment for sister chromatids
What is the difference between cytokinesis in plant and animal cells? ... Animal cells divide by a cleavage furrow. Plant cells divide by a cell plate that eventually becomes the cell wall. Cytoplasm and cell membranes are necessary for cytokinesis in both plants and animals.
Contrast cytokineses in animal cells and plant cells.
Internal Checkpoints During the Cell Cycle: The cell cycle is controlled at three checkpoints. The integrity of the DNA is assessed at the G1 checkpoint. Proper chromosome duplication is assessed at the G2 checkpoint. Attachment of each kinetochore to a spindle fiber is assessed at the M checkpoint.
Describe 3 checkpoints of the cell cycle.
The cell cycle is a 4-stage process consisting of Gap 1 (G1), Synthesis, Gap 2 (G2) and mitosis. An active eukaryotic cell will undergo these steps as it grows and divides. After completing the cycle, the cell either starts the process again from G1 or exits the cycle through G0.
Describe cell cycle, including its different stages.
all but anaphase and telophase
During which mitotic phases are duplicated chromosomes present?
In Cytokinesis, the contractile ring in animal cells contracts and pinches the cell into 2 daughter cells. In plants, the phragmoplast extends and forms the cell wall. In plants, mitosis occurs only in the meristem tissues. They are located at the tips of roots, shoots, and in the stem, between the xylem and phloem.
How does plant cell mitosis differ from animal cell mitosis?
14 because the chromatids separate
If a parent cell has 14 chromosomes prior to mitosis, how many chromosomes will each daughter cell have?
has a single loop of DNA
In contrast to a eukaryotic chromosome, a prokaryotic chromosome...
growth and repair maintaining the chromosome number in all body cells.
In human beings, mitosis is necessary for...
prometaphase
In which phase of mitosis are the kinetochores of the chromosomes being attached to spindle fibers?
spindle
Microtubule structure that brings about chromosome movement during nuclear invasion.
apoptosis occurs frequently during the cell cycle
Not true for cell cycle
metaphase plate
Plane midway between the two poles of the cell where chromosomes line up during metaphase.
apoptosis
Programmed cell death that's carried out by enzymes routinely present in the cell.
RB
Rubidium
G2 stage
The cell synthesizes the proteins needed for cell division
therapeutic cloning
The cloning of human cells by nuclear transplantation for therapeutic purposes, such as the generation of embryonic stem cells to treat disease.
is the 2n number is in a parent cell and therefore in the 2 daughter cells following mitosis varies according to the particular organism is in every somatic cell
The diploid number of chromosomes
prometaphase
The second stage of mitosis, in which the nuclear envelope fragments and the spindle microtubules attach to the kinetochores of the chromosomes.
metastasis
The spread of cancer cells beyond their original site
The radiation caused mutations to occur that can lead to cancer. The number of mutations required varies according to the type of cancer. Cancers that occurred earlier required fewer mutations than those that occurred later.
The survivors of the atomic bombs that were dropped on Hiroshima/Nagasaki have been the subjects of long-term studies of the effects of ionizing radiation on cancer incidence. The frequencies of different types of cancer in these individuals varied across the decades. In the 1950s, high levels of leukemia and cancers of the lung and thyroid gland were observed. The 1960s and 19702 brought high levels of breast and salivary gland cancers. In the 1980s, rates of colon cancer were especially high. Why do you suppose the rates of different types of cancer varied across time?
Characteristics of cancer cells
These cells often undergo angiogenesis tend to be nonspecialized often have abnormal nuclei can metastasize
p53
This tumor suppressor gene causes cell cycle arrest in G1, providing time for DNA repair. If repair is successful, cells re-enter the cycle. If unsuccessful, apoptosis
reproductive cloning
Using a somatic cell from a multicellular organism to make one or more genetically identical individuals.
Cancer cells undergo apoptosis
What's not a characteristic of cancer cells?
telophase---a resting phase between cell division cycles
What's paired correctly?
control of the cell cycle is impaired
When cancer occurs...
proto-oncogene
a gene that regulates normal cell division but that can become a cancer-causing oncogene as a result of mutation or recombination
somatic cell
any cell of a living organism other than the reproductive cells.
cancer
any malignant growth or tumor caused by abnormal and uncontrolled cell division
S stage
at the end of this stage, each chromosome consist of 2 attached chromatids.
oncogene
cancer causing gene
centrosome
central microtubule organizing center of cells, consisting of granular material. In animal cells, it contains 2 centrioles. found at spindle pole in the center of an aster
chromosome
coiled and condensed chromatin
An important difference between oncogenes and tumor suppressor genes is that oncogenes result from the activation (turning on) of proto-oncogenes, but tumor suppressor genes cause cancer when they are inactivated (turned off).Jun 25, 2014
compare/contrast the functions of proto-oncogenes and tumor suppressor genes in controlling the cell cycle.
Cell division is simpler in prokaryotes than eukaryotes because prokaryotic cells themselves are simpler. Prokaryotic cells have a single circular chromosome, no nucleus, and few other cell structures. Eukaryotic cells, in contrast, have multiple chromosomes contained within a nucleus, and many other organelles.Nov 15, 2019
contrast the function of cell division in prokaryotic and eukaryotic cells.
Mitosis consists of four basic phases: prophase, metaphase, anaphase, and telophase. ... These phases occur in strict sequential order, and cytokinesis - the process of dividing the cell contents to make two new cells - starts in anaphase or telophase.
describe the events that occur during the phases of mitosis.
During interphase, the cell copies its DNA in preparation for mitosis. Interphase is the 'daily living' or metabolic phase of the cell, in which the cell obtains nutrients and metabolizes them, grows, reads its DNA, and conducts other "normal" cell functions. This phase was formerly called the resting phase.
describe the preparations for mitosis.
The usual method of prokaryote cell division is termed binary fission. The prokaryotic chromosome is a single DNA molecule that first replicates, then attaches each copy to a different part of the cell membrane. When the cell begins to pull apart, the replicate and original chromosomes are separated.
describe the prokaryotic chromosome and the process of binary fission.
Chromatin is the DNA and proteins that make up a chromosome. ... Histone- they help condense chromatin and DNA into Chromatin. Centromere- they link sister chromatids together. Kinetochore- they attach to opposite poles of the mitotic spindle.
distinguish between chromosome, chromatin, chromatid, centriole, cytokinesis, centromere, and kineticore.
cytokinesis
division of the cytoplasm
M (mitotic) stage
during this stage, daughter chromosomes are distributed to 2 daughter nuclei.
angiogenesis
formation of new blood vessels
malignant
harmful
benign
harmless
Interphase
is composed of G1, S, and G2 stages is the majority of the cell cycle
Abnormally shaped and significantly vary in size. Incapable of self-repair. Do not go through normal apoptosis. Do not perform normal cell functions (as is the case with specialized cells)
list and discuss characteristics of cancer cells that distinguish them from normal cells.
tumor
mass of rapidly dividing cells that can damage surrounding tissue
growth factor
one of a group of external regulatory proteins that stimulate the growth and division of cells
chromatid
one of two identical "sister" parts of a duplicated chromosome
mitosis
part of eukaryotic cell division during which the cell nucleus divides
interphase
period of the cell cycle between cell divisions
asexual reproduction
process of reproduction involving a single parent that results in offspring that are genetically identical to the parent
apoptosis
programmed cell death
histone
protein molecule around which DNA is tightly coiled in chromatin
telomere
repetitive DNA at the end of a eukaryotic chromosome
metaphase
second phase of mitosis, during which the chromosomes line up across the center of the cell
cell cycle
series of events that cells go through as they grow and divide
centriole
structure in an animal cell that helps to organize cell division
sister chromatid
structure that contains identical DNA copies and is formed during DNA replication
cell cycle
the cell cycle is controlled by internal/external signals. cyclin is a signaling molecule that increases and decreases as the cycle continues. DNA damage can stop the cell cycle at the G1 checkpoint.
G1 stage
the cell doubles its organelles and accumulates the materials needed for DNA synthesis
haploid (n) number
the number of homologous pairs in a diploid cell.
anaphase
the third phase of mitosis, during which the chromosome pairs separate and move toward opposite poles
diploid (2n) number
twice the number of chromosomes found in the gametes