Gland Endocrine glands secrete substances that circulate through the blood stream. The glands secrete their products through basal lamina into the blood stream. Basil lamina typically can be seen a layer around the glands to which a million maybe more tiny blood vessels are attached. These glands often secrete hormones which play an important role in maintaining homeostasis. The pineal gland, thymus gland, pituitary gland, thyroid gland, and the two adrenal glands are all endocrine glands. Exocrine glands secrete their products through a duct onto an outer surface of the body, such as the skin or the gastrointestinal tract. Secretion is
History of the location of the soul particular importance to the location of the soul was the 4th ventricle of the brain. In his treatise, "On Anatomy", "pneuma" was inhaled by the lungs and sent to the brain ventricles via the vessels of the body where the brain would convert it into what he called "psychic pneuma", or the soul, and produce thought, motion and all other animations of the body. Herophilus discovered the bumpy aspect of the walls of the ventricles of the brain that he called the choroid plexus and which was thought to be the interaction of the brain with the "pneuma" to create