AP BIOLOGY

Detailed explanation-1: -The majority of signal transduction pathways involve the binding of signaling molecules, known as ligands, to receptors that trigger events inside the cell. The binding of a signaling molecule with a receptor causes a change in the conformation of the receptor, known as receptor activation.

Detailed explanation-2: -Signal transduction is the process in which binding of an extracellular messenger to the cell surface receptor is translated into changes in biochemistry, cell biology, and gene transcription that make it possible for the cell to respond to the information that was received.

Detailed explanation-3: -The widely used RTK signal transduction pathway. The receptor tyrosine kinase is dimerized by the ligand, which causes the autophosphorylation of the receptor.

Detailed explanation-4: -Transduction: When the signaling molecule binds the receptor it changes the receptor protein in some way. This change initiates the process of transduction. Signal transduction is usually a pathway of several steps. Each relay molecule in the signal transduction pathway changes the next molecule in the pathway.