BILD 2 Lecture Notes - Lecture 16: Thyroid, Basal Metabolic Rate, Signal Transduction
Document Summary
Signaling for water-soluble hormones: travel in blood on their own, cannot diffuse across membranes -> bind to receptor on membrane, receptor activates signal transduction pathway -> causes response inside cell. Signaling for lipid-soluble hormones: must travel in blood bound to transport proteins, diffuse through membrane of target cells, receptors either in cytosol or nucleus, receptor/hormone complex acts as a transcription factor. Pituitary divided in 2: posterior: stores and secretes hormones made in hypothalamus, ex: adh and oxytocin, anterior: makes and releases hormones in response to hypothalamic hormones. Major effects of thyroid hormone: affects virtually every cell in the body. Increases how much energy you use at rest (basal metabolic rate) through stimulating cells to use oxygen and make atp: promotes growth and development of nervous, skeletal, and reproductive systems. Thyroid hormone and iodine: thyroid hormone (main form: thyroxine) contains and requires iodine, body can"t make iodine.
