Final answer:
Receptor tyrosine kinases undergo conformational changes and dimerize when exposed to ligands or agonists, leading to autophosphorylation of tyrosine residues and subsequent cellular response.
Step-by-step explanation:
Receptor tyrosine kinases undergo conformational changes and dimerize when exposed to ligands or agonists. This occurs when signaling molecules bind to the extracellular domains of two nearby receptors, causing them to bond together. As a result, tyrosine residues on the intracellular domains of the receptors are autophosphorylated, triggering a downstream cellular response.