Final answer:
Enzyme-coupled receptors, also known as enzyme-linked receptors, are cell-surface receptors that activate enzymes upon ligand binding.
Step-by-step explanation:
Enzyme-coupled receptors, also known as enzyme-linked receptors, are cell-surface receptors with intracellular domains that are associated with an enzyme. When a ligand binds to the extracellular domain of an enzyme-coupled receptor, a signal is transferred through the membrane, activating the enzyme. Activation of the enzyme sets off a chain of events within the cell that eventually leads to a response. Enzyme-coupled receptors are discovered for their role in responding to growth factors in animal cells.