What is a hormone and how does it act? - CORRECT ANSWER Hormones are chemical messengers that are responsible for regulation. They are secreted into body fluids, mainly blood. It has specific actions on target tissues, which are any tissue that has specific receptors for that particular hormone. What is a paracrine gland? - CORRECT ANSWER a secretion that enters interstitial fluid but affects only neighboring cells What is an autocrine gland? - CORRECT ANSWER A secretion that only affects the secreting cell. What is an endocrine gland? - CORRECT ANSWER A gland that secretes a substance (a hormone) into the bloodstream and act on target cells What is an exocrine gland? - CORRECT ANSWER A ducted gland that produces a secretion onto a body surface. Where is the thymus located? - CORRECT ANSWER mediastinum; behind the sternum Where is the pineal gland located? - CORRECT ANSWER center of brain Where are the reproductive organs located? - CORRECT ANSWER abdomen; pelvic Where is the pituitary gland located? - CORRECT ANSWER sella turcica of the sphenoid bone; base of the brain Where are the adrenal glands located? - CORRECT ANSWER on top of each kidney Where is the pancreas located? - CORRECT ANSWER posterior to the stomach What are the two steroid hormones? - CORRECT ANSWER Sex hormones and adrenal cortex hormones; estrogen and testosterone Describe steroid hormones - CORRECT ANSWER -diffuse through cell membranes into cytoplasm or nucleus -combine with a receptor molecule binding to DNA -promote transcription of mRNA -mRNA enters cytoplasm directing protein synthesis Describe non-steroid hormones. - CORRECT ANSWER Amines, proteins, peptides, and glycoproteins. The endocrine gland secretes nonsteroid hormones, which body fluid carries hormone to its target cell. Hormone combines with receptor site on membrane of its target cell, activating G protein. Cellular changes produce the hormone's effects. How is the anterior pituitary gland different than the posterior pituitary gland? - CORRECT ANSWER The anterior pituitary becomes an endocrine gland producing and secreting hormones for the body and connects to the posterior pituitary when fully formed. Meanwhile, the posterior pituitary remains connected to the hypothalamus, functioning as a repository for hormones produced by the hypothalamus and receiving messages from it that regulate when hormones are to be released to and through the anterior pituitary What regulates pituitary gland secretion? - CORRECT ANSWER Hypothalamus Describe tropic hormones - CORRECT ANSWER stimulate other endocrine glands to release hormones anterior pituitary hormones - CORRECT ANSWER ACTH - controls manufacture and secretion of certain hormones from the outer layer of the adrenal gland. FSH - controls growth and development of follicles that house egg cells in ovaries and stimulate production of sperm cells in the testes. GH - stimulates cells to enlarge and more rapidly divide LH - promotes secretion of sex hormones and allows release of egg cells from ovaries PRL - promotes milk production TSH - controls secretion of certain hormones from the thyroid posterior pituitary hormones - CORRECT ANSWER ADH - reduces volume of water that kidneys secrete Oxytocin - smooth muscle contraction and allows contraction of the uterus during childbirth and may stimulate the movement of certain fluids in the male reproductive tract during sexual activity