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