Alberta Biology 30 Cell Division Practice Test

Transcription factors regulate cell division by controlling which genes are turned on or off. They bind to DNA and influence the production of key cell-cycle regulators, especially cyclins and CDKs. Cyclins partner with CDKs to form active enzymes that phosphorylate target proteins, driving the cell cycle forward through the G1/S, S, G2/M transitions, and mitosis. Because the levels of cyclins rise and fall in a timed way, transcription factors help set the order and timing of these transitions. They also coordinate the production of inhibitors or checkpoint proteins that can pause the cycle if DNA is damaged, ensuring division only proceeds when conditions are right. So transcription factors directly influence cell division by regulating the expression of genes like cyclins and CDKs, shaping the progression through the cell cycle.