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
The Green Brain The Green Brain The Green Brain (1966), initially published as Greenslaves, is a science fiction novel by American writer Frank Herbert. The book is set in the not-so-distant future, where humankind has all but succeeded in controlling all life on the planet and almost completely wiping out all insect life. The earth is divided into a "Green Zone" which humans totally dominate (or so they believe) and a diminishing "Red Zone" that is not yet conquered. The "Green Brain" of the title is an intelligent organism that embodies and arises from nature's resistance to human domination. It is able to