BIOCHEM 3H03 Study Guide - Final Guide: Liver Disease, Trachea, Dyslipidemia
Document Summary
Biochem 3h03 lecture notes after the 2 nd midterm. The thyroid gland consists of two lobes connected by a narrow isthmus located on either side of the trachea at the base of the throat. Follicular cells main function: synthesize t3 and t4; and within this system, it stores it. General effect increased metabolic rate: thyroid hormones help increase the effects of catecholamines (fight/flight) T3 is the active form, most t4 converted in peripheral cells to t3: t4 is also secreted but is less active form compared to t3. Crosses cell membrane and binds to nuclear receptor. Mrna and protein synthesis lag time of hours to days for full effect. Fetal brain and skeletal development: fetus depends mostly on fetal hormone. Lack of maternal iodine in diet low hormone levels in mother and fetus. Cardiovascular: increased cardiac motility, heart rate and cardiac output. Sympathetic: increased beta adrenergic receptors in muscle, adipose and lymphocytes (increased sensitivity to catecholamines)