Compare peptide and steroid hormones in terms of solubility, receptor location, and mechanism of action.

• A. Peptide hormones are lipid-soluble and bind intracellular receptors.
• B. Peptide hormones are water-soluble, bind membrane receptors, and use second messengers; steroids are lipid-soluble, bind intracellular receptors, and affect gene transcription.
• C. Peptide hormones require carriers to enter cells; steroids do not.
• D. Both hormone types use the same mechanism.

Answer: (B)