BIOL 2312 Study Guide - Midterm Guide: Paracrine Signalling, Hydrophile, Hyperthyroidism
Document Summary
45. 1 regulation of body processes by chemical messengers: four mechanisms of cell communication. Hormone: regulatory chemical that is secreted into extracellular fluid and carried by blood to its directed target: referred to as endocrine secretions. Endocrine glands: organs that specialize in secreting hormones: some organs (liver & kidney) can also produce hormones in addition to secretion. Exocrine glands: excrete their products into a duct outside the body or into the gut. Ex: sweat glands that excrete sweat outside the body on skin. Ex: pancreas excretes hydrolytic enzymes into the lumen of the small intestine. Paracrine regulators: regulatory chemicals that act within the organ they are used. Autocrine signaling: cells release signaling molecules that affect their own behavior, circulating hormones and neurotransmitters. A molecule produced by endocrine glands and used as a hormone can also be produced and used as a neurotransmitter by neurons: ex: norepinephrine.
