Final answer:
A nonpolar receptor molecule easily penetrates the plasma membrane due to its lipophilic properties and binds with intracellular receptors to influence gene expression.
Step-by-step explanation:
Nonpolar receptor molecules typically penetrate the plasma membrane easily due to their lipophilic nature. Therefore, a nonpolar receptor molecule binds to intracellular receptors rather than needing to utilize membrane channels or carrier proteins. This is because nonpolar (lipid-soluble) molecules can diffuse through the lipid bilayer of the plasma membrane and do not require assistance to enter the cell.
Once inside, they may form a receptor-ligand complex which can move into the nucleus and interact with the DNA, ultimately affecting gene expression. This contrasts with polar molecules, which are unable to cross the plasma membrane without help, due to their hydrophilic nature, and therefore bind to extracellular receptors. The binding of polar ligands to extracellular receptors can result in the activation of secondary messengers within the cell's signaling pathways.