Mastering A&P - Membrane Potential fully solved 2023 already passed

Mastering A&P - Membrane Potential Ions are unequally distributed across the plasma membrane of all cells. This ion distribution creates an electrical potential difference across the membrane. What is the name given to this potential difference? - correct answer Resting Membrane Potential (RMP) Sodium and potassium ions can diffuse across the plasma membranes of all cells because of the presence of what type of channel? - correct answer Leak channels On average, the resting membrane potential is -70 mV. What does the sign and magnitude of this value tell you? - correct answer The inside surface of the plasma membrane is much more negatively charged than the outside surface. The plasma membrane is much more permeable to K+ than to Na+. Why? - correct answer There are many more K+ leak channels than Na+ leak channels in the plasma membrane. The resting membrane potential depends on two factors that influence the magnitude and direction of Na+ and K+ diffusion across the plasma membrane. Identify these two factors. - correct answer The presence of concentration gradients and leak channels What prevents the Na+ and K+ gradients from dissipating? - correct answer Na+-K+ ATPase If the sodium-potassium pumps in the cell membrane of a neuron fail to function, over time.... - correct answer -- the membrane resting potential will become more positive than normal. -- the extracellular concentration of potassium ion will increase. -- the intracellular concentration of sodium ion will increase. Why is the resting membrane potential (Vm) approximately - 70 mV for most cells? - correct answer Most membranes are 40 times more permeable to K+ than to Na+. Voltage-gated (voltage-dependent) channels and antiport carriers are both types of ....? - correct answer transporters Compared to the outside surface, the inside of a resting cell membrane is ...? - correct answer negatively charged As the charge on the membrane of a typical neuron approaches 0 from -70 mV, the cell is ...? - correct answer only depolarizing Which of the following is NOT involved in creating the resting potential of a neuron? A. diffusion of sodium ions into the cell B. resting membrane permeability for sodium ions greater than potassium ions C. resting membrane permeability for potassium ions greater than sodium ions D. diffusion of potassium ions out of the cell - correct answer B. resting membrane permeability for sodium ions greater than potassium ions Be familiar with figure 5.23 - correct answer -- Na+ enters the cell.... A. resting membrane potential B. hyperpolarization C. depolarization D. repolarization E. more than one of the answers - correct answer C. depolarization