When a Signal Is Initiated by the Binding of an Extracellular

Multiple Choice

When a signal is initiated by the binding of an extracellular ligand, what is the immediate outcome of that signal?

A) A protein in the middle of an intracellular signaling pathway is activated.
B) A protein at the top of an intracellular signaling pathway is activated.
C) A protein at the top of an extracellular signaling pathway is activated.
D) A protein at the top of an intracellular signaling pathway is deactivated.
E) A protein at the bottom of an intracellular signaling pathway is activated.