Biology › Section E · Cell communication and the cell cycle › Topic E.3

Signaling in single-celled organisms

Cells learned to talk long before they learned to live together. Yeasts woo each other with mating factors, bacteria count their own numbers with released chemicals and light up when the census is high enough — and the signaling toolkits they use are the same ones your cells use, which is why these microbes still teach biologists how communication works.