Problem 6

Background and context

There are three types of hormones: amino acid-derived, lipid-derived, and peptide. Amino acid-derived hormones are small molecules like epinephrine and norepinephrine. Lipid-derived hormones have structures similar to cholesterol and these include steroid hormones. Peptide hormones include proteins and hormone receptors. 

Steroid hormones are testosterone and estradiol. Estradiol or estrogen is a female sex hormone and testosterone is a male sex hormone. These hormones are released by reproductive organs. Adrenal glands also secrete steroid hormones like aldosterone and cortisol.