Cell cycle
Say it: SEL SY-kul
The cell cycle is the ordered series of growth, DNA copying and division stages that a cell passes through to produce two daughter cells.
Also: cell division cycle, mitotic cycle
Definition
What is the cell cycle?
The cell cycle is the repeating sequence of events from the moment a cell forms to the moment it divides into two. Most of it is interphase, made up of G1, when the cell grows and gathers resources; S phase, when it replicates its DNA; and G2, when it prepares for division. The mitotic phase follows, in which mitosis separates the chromosomes and cytokinesis divides the cytoplasm.
Cells do not simply run through the cycle on a timer. Checkpoints near the end of G1, at the G2-to-M transition and during metaphase verify that the cell is large enough, that its DNA is intact and fully copied, and that every chromosome is attached to the spindle. Proteins called cyclins and cyclin-dependent kinases push the cell past each checkpoint, while brakes such as p53 and the retinoblastoma protein can halt it. Many mature cells, including most nerve cells and heart muscle cells, leave the cycle and stay in a nondividing state called G0.
When these controls fail, cells can divide without restraint, which is why many genes involved in cancer act on the cell cycle.
Word parts
Where does the term “cell cycle” come from?
- cell
- small roomLatin cella
- cycl-
- circle, wheelGreek kyklos
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Related
Terms that go with it
- MitosisMitosis is the division of a cell's nucleus that gives each of two daughter cells an identical, complete set of chromosomes.
- DNA replicationDNA replication is how a cell copies all of its DNA before it divides, so that each daughter cell receives a complete genome.
- Tumor suppressor geneA tumor suppressor gene makes a protein that restrains cell division or repairs damage, so losing both working copies can help a cell turn cancerous.
- OncogeneAn oncogene is a mutated or overactive form of a normal growth-promoting gene that pushes cells to divide uncontrollably and can cause cancer.
- ApoptosisApoptosis is programmed cell death, a controlled process in which a cell dismantles itself in an orderly way without harming its neighbors.
- CancerCancer is a group of diseases in which abnormal cells divide without control, invade nearby tissue and can spread to distant parts of the body.
Sources
Checked against
Written for biofideX in plain words, after checking these references:
- OpenStax Biology 2e, 10.2 The Cell Cycle
- OpenStax Biology 2e, 10.3 Control of the Cell Cycle
- NCI Dictionary of Cancer Terms: cell cycle
- MeSH (NLM): Cell Cycle
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