PSL 311L Study Guide- Questions and Correct Answers

PSL 311L Study Guide - Questions and Correct Answe rs How does temperature influence diffusion? ✅as temperature increases, the time of diffusion increases. heat increases the influence on Brownian motion of molecules and will make them move much faster. as they move faster, they distribute faster. How might the application of heat/ice to an injured body part relate to the above concept in the body? ✅applying ice to a body part decreases the movement of fluid/solutes, therefore reducing the amount of swelling. heat, on the other hand, will increase the fluid/solute movement which will increase the amount of fluid to the injured area causing excessive s welling. How does size of particles influence diffusion? ✅smaller molecules often have an easier time getting across semipermeable membranes than larger molecules How does medium influence diffusion? ✅as the density of a solvent increase, the diffusion rate decreases. if the medium is less dense, diffusion increases. How does concentration influence diffusion? ✅in reference to osmosis, water will flow to wherever the solutes are located. therefore, if there is a higher concentration of solutes on one side of the cell, the water will move toward that side and vice versa. diffusion is the flow from high concentrati on to low concentration How will the concentration of the solution influence fluid movement into/out of cells?✅fluids will move to the more concentrated solution When might a patient be given a hypertonic IV solution (has a higher solute concentration than the cell)? ✅when a person is over -hydrated When might a patient be given a hypotonic IV solution (has a lower solute concentration than the cell)? ✅when the cell is dehydrated and fluids need to be put back intracellularly When might a patient be given an isotonic IV solution (has the same solute concentration as the cell)? ✅an isotonic solution is given to someone to increase the amount of extracellular fluid due to blood loss, surgery, dehydration, and fluid loss that has been lost extracellularly What do you suspect would occur if a patient were given a 3 -5% hypertonic IV solution after being given a typical IV saline solution with 0.9%NaCl? When might a healthcare provider use this solution? ✅it would pull fluid out of the cells and decrease edema, causing red blood cell crenation. this solution might be used by a healthcare provider if a person is experiencing hyponatremia, which is when there are abnormally low sodium levels in the blood. What are causes of hyponatremia (abnormally low levels of sodium in the blood)? ✅1) consumption of a ton of water causing extremely low levels of sodium in the blood 2) dehydration 3) medication 4) heart, kidney, liver problems 5) chronic vomiting/diarrhea What sort of environment does consuming excessive amounts of pure water create in the body fluid that surrounds the cells? What effect would this have on your cells? ✅the environment created in the body fluid surrounding the cells will be hypertonic. this is because with fluid overload, the cells end up containing more solutes than the outside environment. therefore, the water will travel into the cells, via osmosis, ca using them to swell and possibly eventually lyse What are the physiological events that occur between the delivery of stimulus and recorded EMG response? ✅1) an action potential in the peripheral nerve is generated by an electrical stimulus 2) AP is conducted along the nerve axon and causes release of acetylcholine into the synaptic cleft of the neuromuscular junction 3) acetylcholine diffuses through the junctional cleft and binds to nicotinic acetylcholine receptors on the motor end plate 4) the bound receptors open cation -selective ion channels, depolarizing the muscle end plate 5) this sets up muscle AP that leads to the release of calcium from the sarcoplasmic reticulum 6) the increased cytosolic calcium sets in motion the biochemical events that underlie contraction 7) acetylcholine is rapidly hydrolyzed by acetylcholine esterase that terminates the endplate potentials What variables/nerve characteristics would change nerve conduction velocity? ✅decrease nerve conduction velocity: