Adrenal gland
The adrenal glands are named for their location relative to the kidneys. The term "adrenal" comes from "ad-" (Latin, "near") and "renes" (Latin, "kidney"). Similarly, "suprarenal", as termed by Jean Riolan the Younger in 1629, is derived from the Latin "supra" () and "renes" (). The suprarenal nature of the glands was not truly accepted until the 19th century, as anatomists clarified the ductless nature of the glands and their likely secretory role – prior to this, there was some debate as to whether the glands were indeed suprarenal or part of the kidney.
Behavioral endocrinology
thyroxine (T4) and triiodothyronine (T3) are the main hormones released in the thyroid gland. They are synthesized from tyrosine and iodine in the blood stream. 
These hormones travel via bloodstream to almost every cell throughout the body and function to regulate their target cell's metabolism. These hormones are a product of the hypothalamic–pituitary–adrenal axis (HPA axis or HTPA axis). These organs function together as the hypothalamus releases thyrotropin releasing hormone (TRH), which cause the pituitary gland to secrete thyrotropin that signal the thyroid gland to process and release thyroxine and triiodothyronine to the body. These hormones play a major role in the Neuroendocrine system which regulates the vital body functions of breathing, body weight, heart rate, muscle strength, cholesterol levels, especially body temperature. When your body has to much or too little of these hormones it has abnormal affect throughout your body: