All of the following hormones have cell surface receptors except:
**Core Concept**
Steroid hormones, such as cortisol, aldosterone, and progesterone, are lipophilic molecules that can diffuse through the cell membrane and bind to intracellular receptors. These intracellular receptors then translocate to the nucleus to regulate gene expression. In contrast, peptide hormones, such as insulin, growth hormone, and thyroid-stimulating hormone (TSH), have cell surface receptors that trigger intracellular signaling cascades.
**Why the Correct Answer is Right**
The correct answer is likely a steroid hormone, which diffuses through the cell membrane and binds to an intracellular receptor. This is in contrast to peptide hormones, which have cell surface receptors. For example, insulin binds to the insulin receptor on the surface of cells, triggering a phosphorylation cascade that activates downstream signaling pathways.
**Why Each Wrong Option is Incorrect**
**Option A:** This option might be a peptide hormone, such as vasopressin, which has a cell surface receptor. Vasopressin binds to the V2 receptor in the renal collecting duct, leading to increased water reabsorption.
**Option B:** This option might be a peptide hormone, such as atrial natriuretic peptide (ANP), which has a cell surface receptor. ANP binds to the guanylyl cyclase-linked receptor, leading to decreased blood pressure and increased sodium excretion.
**Option C:** This option might be a steroid hormone, such as cortisol, which diffuses through the cell membrane and binds to an intracellular receptor. Cortisol binds to the glucocorticoid receptor, leading to increased gluconeogenesis and lipolysis.
**Clinical Pearl / High-Yield Fact**
Steroid hormones can be distinguished from peptide hormones based on their mechanism of action. Steroid hormones diffuse through the cell membrane and bind to intracellular receptors, while peptide hormones have cell surface receptors.
**Correct Answer: C. Cortisol**