The cell cycle allows multiicellular organisms to grow and divide and single-celled organisms to reproduce.
The genome of an organism consists of its entire complement of DNA, which encodes the genes that control the organism's characteristics.
Eukaryotic Chromosomal Structure and Compaction
Chromosomes must coil to pack DNA into the cell during cell division, a process involving 3 levels of compaction.
The Cell Cycle
Cells must grow and duplicate their internal structures during interphase before they can divide during mitosis.
The Mitotic Phase and the G0 Phase
During the multistep mitotic phase, the cell nucleus divides, and the cell components split into two identical daughter cells.
Control of the Cell Cycle
Regulation of the Cell Cycle by External Events
External factors can influence the cell cycle by inhibiting or initiating cell division.
Regulation at Internal Checkpoints
The cell cycle is controlled by three internal checkpoints that evaluate the condition of the genetic information.
Regulator Molecules of the Cell Cycle
The cell cycle is controlled by regulator molecules that either promote the process or stop it from progressing.
Cancer and the Cell Cycle
Proto-oncogenes normally regulate cell division, but can be changed into oncogenes through mutation, which may cause cancers to form.
Tumor Suppressor Genes
Tumor-suppressor genes keep regulatory mechanisms of cell division under control and prevent abnormal cell growth.
Prokaryotic Cell Division
Binary fission is the method by which prokaryotes produce new individuals that are genetically identical to the parent organism.