Where are receptors for protein hormones located in a cell?

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Hormone Many important physiological functions of vertebrates are controlled by steroid hormones.

Receptors for protein and peptide hormones are located on the surface of target cells. Because these hormones are highly soluble in water, they cannot easily cross the cell membrane; therefore, they bind to specific receptors embedded in the cell membrane, with the binding region facing the exterior of the cell.12

In contrast, receptors for steroid and thyroid hormones are typically found within the cytoplasm or nuclei of target cells, as these molecules are able to cross the cell membrane to reach their binding sites.12