The main difference between the modes of action of peptide hormones and steroid hormones is that
A)Peptide hormones bind to intracellular receptors whereas steroid hormones bind to receptors on the cell surface
B)Peptide hormones bind to receptors in the nucleus whereas steroid hormones bind to receptors in the cytosol
C)Peptide hormones bind to receptors on the cell surface whereas steroid hormones act as second messengers
D)Peptide hormones bind to receptors on the cell surface whereas steroid hormones bind to intracellular receptors
E)There are no differences; both act by binding to receptors on the cell surface

Question

Quizplus · Accepted Answer

Peptide hormones bind to receptors on the cell surface, whereas steroid hormones bind to intracellular receptors. Peptide hormones are water-soluble, and therefore cannot pass through the cell membrane. They bind to specific receptors on the cell membrane, and activate intracellular signaling pathways through second messengers such as cyclic AMP. Steroid hormones, on the other hand, are lipid-soluble and can pass through the cell membrane. They bind to specific receptors in the cytosol or nucleus of the cell and activate gene expression.

The Main Difference Between the Modes of Action of Peptide