stage of mitosis during which the two sets of chromosomes separate and move away from each other. composed of anaphase A (chromosomes move toward two spindle poles) and anaphase B (spindle poles move apart).
anaphase promoting complex (APC)
a protein complex that promotes the destruction of specific proteins, by catalyzing their ubiquitylation. it is a crucial component of the cell cycle control system.
normal, benign type of programmed cell death in which a cell shrinks, fragments its DNA, and alters its surface so as to activate the cell's phagocytosis by microphages.
star-shaped system of microtubules emanating from a centrosome or from a pole of a mitotic spindle.
family of intracellular proteins that either promote or inhibit apoptosis by regulating the activation of caspases.
the symmetrical alignment of sister chromatids on the mitotic spindle, such that one chromatid is attached to one spindle pole and the other chromatid to the opposite pole.
a family of proteases. members of the family are activated as part of the pathway leading to apoptosis.
Cdk (cyclin-dependent protein kinase)
protein kinase that has to be complexed with a cyclin protein in order to act. different Cdk-cyclin complexes trigger different steps in the cell-division cycle by phosphorylating specific target proteins.
Cdk inhibitor protein
protein that inhibits cyclin-Cdk complexes, primarily to inhibit progress though the G1 and S phases of the cell cycle.
reproductive cycle of the cell: the orderly sequence of events by which a cell duplicates its contents and divides into two.
cell-cycle control system
network of regulatory proteins that governs progression of a eukaryotic cell through the cell cycle.
centrosome (cell center)
centrally located organelle of animal cells that is the primary microtubule-organizing center and separates to form the two spindle poles during mitosis. in most animal cells it contains a pair of centrioles.
duplication of the centrosome (during interphase) and separation of the two new centrosomes (at the beginning of mitotsis), to form the poles of the mitotic spindle.
point in the eukaryotic cell-division cycle where progress through the cycle can be halted until conditions are suitable for the cell to proceed to the next stage.
process by which a chromosome becomes packed into a more compact structure prior to M phase of the cell cycle.
protein complex that forms a ring that holds sister chromotids together after DNA has been replicated in the cell cycle.
protein complexes with a ring-like structure that help carry out chromosome condensation.
protein that periodically rises and falls in concentration in step with the eukaryotic cell cycle. Cyclins activate specific protein kinases and thereby help control progression from one stage of the cell cycle to the next.
division of the cell cytoplasm of a plant or animal cell into two, as distinct from the division of its nucleus (which is mitosis).
cyclin-dependent kinase whose activity drives the cell through G1 phase.
Gap 1 phase of the eukaryotic cell cycle, between the end of cytokinesis and the start of DNA synthesis.
Gap 2 phase of the eukaryotic cell cycle, between the end of DNA synthesis and the beginning of mitosis.
cyclin-dependent kinase whose activity triggers entry into the S phase of the cell cycle.
extracellular polypeptide signaling molecule that stimulates a cell to grow or prolifereate. examples are epidermal growth factor (EGF) and platelet-dervived growth factor (PDGF).
long period of the cell cycle between on mitosis and the next. includes G1 phase, S phase, and G2 phase.
complex protein-containing structure on a mitotic chromosome to which microtubules attach. The kinetochore forms on the part of the chromosome known as the centromere.
active protein complex formed at the start of M phase of the cell cycle by an M-cyclin and the mitotic Cdk.
cyclin protein that binds to mitotic Cdk to form M-Cdk at the start of M phase of the cell cycle.
period of the eukayotic cell cycle during which the nucleus and cytoplasm divide.
stage of mitosis at which chromosomes are firmly attached to the mitotic spindle at its equator but have not yet segregated toward opposite poles.
an extracellular signal molecule that stimulates cell proliferation.
division of the nucleus of a eukaryotic cell, whcih involved condensation of the DNA into visible, chromosomes.
array of microtubules and associated molecules that forms between the opposite poles of a eukaryotic cell during mitosis; during the separation of the duplicated chromosomes, the spindle serves to move the two chromosome sets apart.
origin recognition complex (ORC)
large protein complex that is bound to the DNA at the origins of replication in eukaryotic chromosomes thought the cell cycle.
regulartory protein that responds to the presence of DNA damage, preventing the cell from entering S phase until the damage has been repaired.
structure made of microtubules and membrane vesicles that forms in the equatorial region of a dividing plant cell and from which the membrane that divides the daughter cells will be made.
programmed cell death
stage of mitosis that precedes metaphase.
first stage in mitosis during which the chromosomes are condensed but not yet attached to a mitotic spindle.
period during a eukaryotic cell cycle in which DNA is synthesized.
one copy of a chromosome (a chromotid) formed by DNA replication that is still joined at the centromere to the other copy, the pair of chromotids being known as sister chromotids.
one of two centrosomes in a cell undergoing mitosis. microtubules radiating from these centrosomes form the mitotic spindle.
extracellular signaling molecule that must be present to prevent apoptosis.
final stage in mitosis in which the two sets of separated chromosomes decondense and become enclosed by nuclear envelopes.