parathyroid gland anatomy

parathyroid thyroid gland hormone pth vector calcium parathormone structure homeostasis hypothyroidism metabolism anatomy secretion diagram educational illustration labeled human system parathyrin endocrine hypocalcemia ca d regulation vitamin biology medicine organ anatomical internal hormonal poster clinic graphic design t3 t4 triiodothyronine thyroxine adrenal kidney blood bone gut vessel infographic biochemistry feedback