Chapter 12: The Cell Cycle Flashcards
Cell Reproduction
ability of an organism to make more of its own kind
Cell cycle
life of a cell from formation to its own division
Reproduction
Process of giving rise to another organism
Cell division: prokaryotic and single celled orgs
used for reproduction (by dividing to give rise to another organism)
Cell division: eukaryotic and multicellular orgs
used for:
development
growth
repair
Types of cell division
Binary Fission
Mitosis
Meiosis
Cell division: binary fission
plasma membrane pinches inward, dividing, results in genetically identical dgt cells
Bacteria and archaea do it
Cell division: mitosis
results in genetically identical dgt cells
Cell division: meiosis
results in 2 dgt cells which each only have half of the parent cell’s genetic material
Gamete
sperm and egg cells
have half the chromosomes as a somatic/parent cells
Genome
all DNA in a cell
Somatic cells
nonproductive cells; have two sets of chromosomes
centromere
Narrow “waist” of the chromosome
Cell cycle phases (5)
Interphase
Mitotic (M) phase
Cell cycle phases: Interphase
G1 first gap
S synthesis
G2 second gap
Cell cycle phases: Mitotic M phase
mitosis (division of nucleus)
cytokinesis (division of cytoplasm)
Cell cycle phases: Mitotic M phase: Mitosis
Prophase Prometaphase Metaphase Anaphase Telophase and cytokinesis
kinetochores
protein complexes associated with centromeres
Mitotic spindle
structure made of microtubules that controls chromosome movement during mitosis
aster
radial array of short microtubules
checkpoints
“points” where the cell cycle stops until it receives a go-ahead signal
3 checkpoints
G1
G2
M
G0 phase
When a cell stops its division cycle and goes into a non dividing state
Cyclin dependent kinases (Cdks)
regulatory protein involved in cell cycle control
Active during G1, S, and G2 phase, accumulating cyclin???
Cyclin
regulatory protein involved in cell cycle control
Maturation Promoting Factor (MPF)
cyclin-cdl complex that triggers a cell’s passage past the G2 checkpoint into the M phase
Growth factors
external factors that influence cell division
released from certain cells to stimulate other cells to divide
Density-dependent inhibition
1 of 2 mechanisms for regulating optimal density of cells
Anchorage dependence
2 of 2 mechanisms for regulating optimal density of cells
Density-dependent inhibition
1 of 2 mechanisms for regulating optimal density of cells
cells divide in a single layer to fill a gap, but stop dividing once the gap gets filled/crowded
Anchorage dependence
2 of 2 mechanisms for regulating optimal density of cells
when cells require a surface for division/must be attached
Cancer cells
May not need growth factors to divide (bc they may be able to make their own or be able to fake them)
Do not yield to regulating mechanisms
Transformation
When a normal cells is turned to a cancer cell
mitosis
(division of nucleus)
cytokinesis
(division of cytoplasm)
Maturation Promoting Factors (MPF)
cyclin -cdk complex that triggers a cell’s passage past the G2 checkpoint to the M phase (in interphase)