Bio 220 Exam 1 | Questions with 100% Correct Answers | Verified | Latest Update 2024

All physiology is a combination of __ mechanisms. - homeostatic Homeostatic mechanisms can be a __ mechanism or a __ mechanism. - positive feedback; negative feedback What is a positive feedback mechanism? - movement away from a standard which encourages more movement away with no attempt to bring it back; could ultimately lead to catastrophic condition and death What is a negative feedback mechanism? - most common homeostatic mechanism; have a standard that we are trying to maintain; digress from this standard as a response to stimuli in the environment; mechanism allows us to come back to the standard; digression from and return to a standard The tendency of a living body to maintain relatively stable internal conditions in spite of greater changes in its external environment is known as... - homeostasis Describe "little loop" - 1. get up in the morning and have a snickers and a Dr. Pepper = digressing from standard (fasting glucose level in this case) towards more glucose level in blood 2. sensor = beta cells in islets of langerhahn in pancreas 3. Beta cells release insulin (water soluble hormone) which travels to target cell in blood via capillaries, binds to receptor resulting in glucose entering cell for cellular respiration thereby lowering blood glucose levels 4. mechanism has worked (recognized this digression and brought it back to the standard