Bio 220 - Exam 1 Questions And Correct Answers| Pass Guaranteed.

All physiology is a combination of __ mechanisms. - correct answer homeostatic Homeostatic mechanisms can be a __ mechanism or a __ mechanism. - correct answer positive feedback; negative feedback What is a positive feedback mechanism? - correct answer 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? - correct answer 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... - correct answer homeostasis Describe "little loop" - correct answer 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 A monosaccharide aka blood sugar is __. - correct answer glucose __ is the noncellular portion of blood. - correct answer plasma Which organelle is responsible to judging the glucose in the blood? - correct answer pancreas What portion of the pancreas is responsible for judging the glucose in the blood? - correct answer islets of langerhahn Which type of cells are in the islets of langerhahm? - correct answer beta cells What is insulin? - correct answer water soluble hormone = goes into blood through capillaries = that lowers blood sugar levels by traveling to the target cell via the blood and binding to a receptor on the cell membrane that allow glucose to enter the cell thereby lowering blood sugar level What is the fasting glucose level? - correct answer The level go glucose that is expected first thing in the morning = 90mg / 100mL The end result of the docking of insulin to its receptor is that __ is taken out of the environment and pulls it into the cell. - correct answer glucose If you can move from a standard and continue to digress further and further away, this is called a __ mechanism. - correct answer positive feedback Cutting your finger is a good example of a __ feedback mechanism - correct answer positive What type of feedback is more common? - correct answer negative If you have a standard, digress from it, and a mechanism brings you back this would be called a __ mechanism. - correct answer negative Is the receptor on the cellular membrane for insulin the same for glucogen? - correct answer no What is short loop? - correct answer when one side of a model is considered What is long loop? - correct answer when both sides of a model are considered A hormone recreated by alpha cells of the pancreatic islets in response to hypoglycemia; promotes glycogenolysis and other effects that raise blood glucose concentration is called... - correct answer glucogen What is the zipper-like junction between epithelial cells that lifts the passage of substances between them? - correct answer tight junction A patch-like intercellular junction that mechanically links two cells together is called a... - correct answer demosome The cell's __ usually dictates function. - correct answer shape An ion pore connecting one cell to another - correct answer gap junction Where can microvilli be found? - correct answer apical surface of simple columnar epithelial cells lining the intesting What do microvilli do? - correct answer increase surface area for increased secretion and absorption Where can cilia be found? - correct answer pseudo stratified columnar epithelial cells lining the respiratory system What do cilia do? - correct answer In the lungs, cilia sweep the layer of mucus that traps dirt particles and moves them toward the throat to be coughed up or swallowed Where can flagella be found and what do they do? - correct answer only found on the sperm cell, allowing motility What are the 9 organelles in a generic cell? - correct answer 1. ER 2. mitochondria 3. Golgi apparatus 4. lysosomes 5. nucleus 6. peroxisomes 7. ribosomes 8. cell membrane 9. polyribosomes spontaneous net movement of particles from a place of higher concentration to a place of lower concentration - correct answer diffusion the net movement of a solute through a cellular membrane against its concentration gradient, involving a carrier protein that expends ATP - correct answer active transport What is a cell membrane made of? - correct answer phospholipid bilayer the net diffusion of water through a selectively permeable membrane - correct answer osmosis having higher osmotic pressure than a solution causing the shrinkage of cells - correct answer hypertonic having lower osmotic pressure than a solution causing the swelling of cells - correct answer hypotonic Having the same osmotic pressure as a solution - correct answer isotonic What does a cell membrane do? - correct answer controls transport and integrity the transport of fluid into a cell by means of local inholdings by the cell membrane so that a vesicle or sac forms around each droplet which is taken into the cytoplasm - correct answer pinocytosis