Biology 2260 Chapter 17 Review Questions with Correct Answers

Compare and contrast the actions of the endocrine system and the nervous system to control body function Endocrine: slow reaction time, communicates by hormones, stimulates cells that hold receptor for hormone, causes metabolic rate change in target cell, widespread effect, long term Nervous System: fast reaction time, communicates by neurons, stimulates other neurons, causes stimulate of cell, localized effect, short term General functions controlled by endocrine system - regulating development, growth and metabolism - maintaining homeostasis of blood composition and volume - controlling digestive processes - controlling reproductive activities Identify the major endocrine glands and their location within the body - some glands are "epithelial organs" with solely endocrine function Ex: pituitary gland, pineal, thyroid, parathyroid and adrenal - some "glands" are clusters of cells in organs with other function Ex: hypothalamus, skin, thymus, heart , liver, stomach, pancreas Explain the 3 major reflex mechanisms for regulating secretion of hormones Hormonal - gland cell releases its hormone when other hormones bind to it Humoral - gland cell releases its hormone when there is a certain change in levels of a nutrient or ion in the blood Nervous - a gland cell releases its hormone when a neuron stimulates it Is the entire pancreas an endocrine organ? no, most of it is exocrine and the endocrine portion is made up of islet cells Parathyroid hormone is secreted when blood calcium levels drop too low. What sort of stimulation is this? humoral Distinguish the hormones that are lipid soluble from those that are water soluble. Lipid soluble: Steroids and eicosanoids