Final answer:
Steroid hormones, which include estrogens, androgens, and glucocorticoids, are synthesized from cholesterol and regulate various physiological processes by binding to specific receptors and influencing gene transcription.
Step-by-step explanation:
Steroid hormones are a group of hormones that include estrogens, androgens, and glucocorticoids . These hormones are synthesized from cholesterol and share structural similarities with it. The liver synthesizes cholesterol, which serves as a precursor to many steroid hormones such as testosterone (an androgen) and estradiol (an estrogen). These hormones are secreted by gonads and endocrine glands and play pivotal roles in various physiological processes, including sexual development, reproductive cycling, salt and mineral homeostasis, and gene regulation.
Steroid hormones are insoluble in water, hence they travel through the bloodstream bound to transport proteins, which prolongs their half-life compared to peptide hormones like epinephrine. Steroid hormones such as cortisol and aldosterone, apart from sex hormones, are also released by the adrenal glands.
The steroid hormones exert their biological effects by diffusing across cell membranes and binding to specific receptor proteins to form a complex that can regulate gene transcription. This complex binds to DNA sequences known as response elements to activate or repress the transcription of target genes.