Final answer:
Steroidal hormones are derived from cholesterol and include key hormones such as testosterone and cortisol. These lipid-derived hormones have a structure similar to cholesterol and can diffuse across cell membranes, with their effects lasting longer than those of water-soluble hormones.
Step-by-step explanation:
Steroidal hormones are derived from cholesterol. These include the reproductive hormones like testosterone and estrogens, which are produced by the gonads (testes and ovaries), and adrenal gland hormones such as aldosterone and cortisol. Steroid hormones, being lipid-soluble, can diffuse across cell membranes and their receptors are usually located inside the target cells.
Lipid-derived hormones like steroid hormones are structurally similar to cholesterol and are usually ketones or alcohols with chemical names ending in "-ol" for alcohols or "-one" for ketones. Examples include estradiol and testosterone. These hormones are non-polar, allowing them to remain in circulation longer than water-soluble hormones, like peptide hormones, which cannot diffuse through cell membranes.
Cholesterol serves as a precursor to many steroid hormones, demonstrating the significant role it plays in the endocrine system.