How do receptor tyrosine kinases function within cellular signaling pathways?

Receptor tyrosine kinases are proteins on the cell surface that receive signals from outside the cell and activate a series of chemical reactions inside the cell. When a signaling molecule binds to the receptor, it triggers the receptor to add phosphate groups to specific tyrosine residues on itself and other proteins, leading to the activation of various signaling pathways that regulate cell growth, division, and survival.