Human Physiology
15th Edition
ISBN: 9781259864629
Author: Fox, Stuart Ira
Publisher: Mcgraw-hill Education,
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Chapter 6, Problem 36RA
Summary Introduction
To analyze:
The following:
The equilibrium potential for potassium or K+ (EK) when its extracellular concentration rises from 5mM (millimolar) to 10mM.
Whether the change is a depolarization or a hyperpolarization compared to normal EK.
Introduction:
The intracellular and extracellular fluids have different inorganic ions and they are maintained at specific concentration. When the concentration is changed, an action potential is produced by each ion across the plasma membrane and is known as membrane potential. The membrane potential is generally determined by K+ ion concentration across the membrane because the plasma membrane is more permeable to K+ ions than any other ions.
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Chapter 6 Solutions
Human Physiology
Ch. 6 - Describe the distribution of fluid in the body.Ch. 6 - Describe the composition of the extracellular...Ch. 6 - List the subcategories of passive transport and...Ch. 6 - Explain what is meant by simple diffusion and list...Ch. 6 - Prob. 4CPCh. 6 - Prob. 5CPCh. 6 - Explain how the body detects changes in the...Ch. 6 - Prob. 7aCPCh. 6 - Prob. 7bCPCh. 6 - Prob. 7cCP
Ch. 6 - Prob. 8CPCh. 6 - Prob. 9aCPCh. 6 - Prob. 9bCPCh. 6 - Explain the relationship of the resting membrane...Ch. 6 - Prob. 10bCPCh. 6 - Prob. 11CPCh. 6 - Prob. 12CPCh. 6 - The movement of water across a plasma membrane...Ch. 6 - Which of these statements about the facilitated...Ch. 6 - Prob. 3RACh. 6 - Prob. 4RACh. 6 - Blood plasma has an osmolality of about 300 mOsm....Ch. 6 - Prob. 6RACh. 6 - The most important diffusible ion in the...Ch. 6 - Prob. 8RACh. 6 - Prob. 9RACh. 6 - Prob. 10RACh. 6 - Prob. 11RACh. 6 - Prob. 12RACh. 6 - Prob. 13RACh. 6 - Prob. 14RACh. 6 - Which of the following questions regarding second...Ch. 6 - Prob. 16RACh. 6 - Prob. 17RACh. 6 - Compare the resting membrane potential of a neuron...Ch. 6 - Prob. 19RACh. 6 - Prob. 20RACh. 6 - Prob. 21RACh. 6 - Prob. 22RACh. 6 - Using the principles of osmosis, explain why...Ch. 6 - Prob. 24RACh. 6 - Prob. 25RACh. 6 - Prob. 26RACh. 6 - Prob. 27RACh. 6 - Prob. 28RACh. 6 - Prob. 29RACh. 6 - Prob. 30RACh. 6 - Using only the information in this chapter,...Ch. 6 - Prob. 32RACh. 6 - Prob. 33RACh. 6 - Suppose a semipermeable membrane separates two...Ch. 6 - Prob. 35RACh. 6 - Prob. 36RACh. 6 - Use the Nernst equation and the ion concentration...
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- The ion flows across neuronal membranes at rest and duringan action potential do not significantly change bulk ionconcentrations, except for that of Ca2+ ions. Resting Ca2+ ionconcentrations in cells are usually about 10–7 M, and Ca2+ ionsexert physiological effects at concentrations of perhaps 10–5 M.Explain why relative changes of intracellular [Ca2+] are muchgreater than for, say, [Na+] (12–50 mM).arrow_forwardThe normal concentrations for intracellular and extracellular potassium in a neuron are [K+]in = 150 mM and [K+]out = 5 mM, respectively. Due to an electrolyte imbalance, a patient has the following intracellular and extracellular concentrations of potassium: [K+]in = 140 mM and [K+]out =2 mM. Using the Nernst equation (Chapter 4), calculate the equilibrium potential for potassium in the cells with normal K+ distributions and of the diseased patient. Refer back to Question #1. Will it be easier or more difficult to generate an action potential in the diseased neuron as compared to the normal neuron? Why?arrow_forwardA cell has an actual membrane potential (Em) at rest of -75mV. The equilibrium potential for Na+ is +120mV and the equilibrium potential for K+ is -95mV. Calculate the net driving force for Na+ in mV.arrow_forward
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