cell bio

state of mitosis during which the two sets of chromosomes separate and move away from each other. composed of anaphase A (chromosomes move toward the two spindle poles) and anaphase B (spindle poles move apart)

a protein complex that promotes the destruction of sepcific proteins, by catalyzing their ubiquitylation. it is a crucial component of the cell cyle 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 cells phagocytosis by macrophages

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 alighnment of sister chromatid pairs 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

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 phosphorylatng specific target proteins

protein that inhibits cyclin-cdk complexes, primarliy to inhibit progress through the g1 and s phases of the cell cycle

reproductive cycle of the cell; the orderly sequence of events by which a cell duplicated its contents and divides into two

network of regulatory proteins that governs progression of a eucaryotic cell through the cell cycle

centrally located organelle of animal cells that is the primary microtubule-organizing center and separates to form the two spindle poles during mitosos. in most ansimal cells it contains a pair of centrioles

duplication of the centrosome (during interphase) and separtation of the two new centrosomes (at the beginning of mitosis) to form the poles of the mitotic spindle

point in the eucaryotic cell division cell cyle 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 complx that forms a ring that holds sister chromatids together after DNA has been replicated in the cell cycle

protein complexes wiht a ring-like structure that help carryout chromosome condensation

protein that periodically rises and falls in concentration in step with the eucarytoic cell cycle. cyclins activate specific protein kinases and thererby help control progression from one stage of the cell cycle to the next

division of the 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 the g1 phase

cyclin dependent kinase whose activity triggers entry into S phase of the cell cycle

gap 1 phase of teh eucaryotic cell cycle, between the end of cytokinesis and the start of DNA synthesis

gap 2 phase of the eucaryotic cell cycle, between the end of DNAsynthesis and the beginning of mitosis

extracellular polypeptide signaling molecule that stimulates a cell to grow or proliferate. examples are epidermal growth factor (EGF) and platelet-derived growth factor (PDGF)

long period of the cell cycle between one mitosis and the next. includes g1 phase, s phase, and g2 phase

complex protein-containing structure on a mitotic chromosome to which microtubels attach. it forms on th epart of the chromosome known as the centromere

active protein complex formed at the start of the M phase of the cell cycle by an M-cyclin and the mitotic cylindependent protein kinase (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 eucaryotic 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 eucaryotic cell, which involves condensation of the DNA into visible chromosomes

array of microtubles and associated molecules that forms between the opposite poles of a eucaryotic cell during mitosis; during the separation of the duplicated chromosomes, the spindle serves to move the two chromose sets apart

large protein complex that is bound to the DNA at origins of replication in eucaryotic chromosomes throughout the cell cycle

regulatory 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 microtubles and membrane vesicles that forms in the equatorial region of a dividing plant cell from which the membrane that divides the daughter cells will be made

state of mitosis that precedes metaphase

first stage of mitosis during which the chromosomes are condensed by not yet attached to a mitotic spindle. also a superficially similar state in meiosis.

period during a eucaryotic cell cycle in which DNA is sythesized

one copy of a chromosome formed by DNA replication that is still joined at the centromere to the other copy, the pair of chromatids being known as sister chromatids

one of two centromsomes ina cell undergoing mitosis. microtubles radiation from these centrosomes form the mitotic spindle

extracellular signaling molecule that must be present to prevent apoptosis

final stage of mitosis in which the two sets of separated chromosomes decondense and become enclosed by nuclear envelopes