Endocrine System: Biochemistry, Secretion, and Transport of Hormones

Catecholemines are produced in the medulla of the adrenal gland and are classified as amine hormones since they are derived from tyrosine. Stimulation of the chromaffin cells causes an influx of calcium ions, which causes the vesicles to merge with the plasma membrane and release the hormone by exocytosis. Are catecholemines water-soluble or lipid-soluble? Water soluble

4. Thyroid hormones include two molecules called T4 (thyroxine) and T3 (triiodothyronine). T3 consists of two tyrosine molecules plus 3 iodine molecules and is ( less) abundant than T4. Are carriers required for the transport of thyroid hormones. No, they are lipid soluble.

Well that was fun! I'm in training for USA Biology Olympiad and this question definitely falls under my range of knowledge.

Thanks so much!!!