sparknotes
The Cell Cycle
Terms
Cell Cycle
-
The two-phase cycle during which a cell replicates its DNA, divides, and then
goes through the processes necessary to replicate DNA, etc. Cell cycles can
vary in duration from 8 minutes to 1 year, though the general duration is around
24 hours for fast-dividing mammal cells. The two phases of the cell cycle are interphase and mitosis.
Cyclin-dependent protein kinase
-
A protein found in eukaryotic
cells responsible for regulating progression through the cell cycle. Must
be complexed with cyclins in order to be active.
Cyclin
-
A protein found in eukaryotic
cells that continually goes through cycles of synthesis and degradation during
the cell cycle. When synthesizes, cyclins activate
cyclin-dependent protein
kinases. Cyclins are synthesized or degraded according to the cells readiness
to move into the next stage of the cell cycle.
G0
-
A sub-phase of G1. Cells in G1 that are not ready to progress in the cell
cycle enter G0 for extended periods of time until they are ready to proceed. G0
can vary in length from minutes to years.
G1
-
The first part of interphase, between the end of mitosis and the beginning of
S phase. A period in which cells grow and make preparations for DNA
replication in S
phase.
G2
-
The final part of interphase, between the end of S phase and the
beginning of mitosis. G2 is an intermediate phase during which cells make
certain they are ready to enter into mitosis.
Interphase
-
The longer of the two phases of the
eukaryotic cell cycle that
includes the sub-phases G1, S phase, and G2. Mitosis is the
second phase of the cell cycle.
Mitosis
-
The shorter phase of the two-phase
eukaryotic cell cycle; cells
divide during mitosis. Interphase is the second phase of the cell cycle.
S phase
-
The second, middle part of interphase, occurring between G1 and G2; during S phase DNA is
duplicated before cell division.




