Hormones are chemical messengers that can be classified based on their solubility. Some hormones, such as progesterone, are lipid-soluble steroids, whereas others, such as adrenaline or insulin, are hydrophilic proteins or peptides.
Suggest the location of the receptors for lipid-soluble steroid hormones and state a reason for your suggestion.
State the location of the receptors for hydrophilic peptide hormones and explain why their location differs from that of steroid hormone receptors.
Explain how a peptide hormone, transportable in the blood but unable to enter the target cell, can still stimulate a change in the internal activity of that cell.