APHY 102 Midterm Exam QUESTIONS AND ANSWERS

APHY 102 Midterm Exam QUESTIONS AND ANSWERS What is a hormone and how does it act? - 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? - ANSWER a secretion that enters interstitial fluid but affects only neighboring cells What is an autocrine gland? - ANSWER A secretion that only affects the secreting cell. What is an endocrine gland? - ANSWER A gland that secretes a substance (a hormone) into the bloodstream and act on target cells What is an exocrine gland? - ANSWER A ducted gland that produces a secretion onto a body surface. Where is the thymus located? - ANSWER mediastinum; behind the sternum Where is the pineal gland located? - ANSWER center of brain Where are the reproductive organs located? - ANSWER abdomen; pelvic Where is the pituitary gland located? - ANSWER sella turcica of the sphenoid bone; base of the brain Where are the adrenal glands located? - ANSWER on top of each kidney Where is the pancreas located? - ANSWER posterior to the stomach What are the two steroid hormones? - ANSWER Sex hormones and adrenal cortex hormones; estrogen and testosterone Describe steroid hormones - 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. - 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.