Study Guide for Campbell Biology
11th Edition
ISBN: 9780134443775
Author: Lisa A. Urry, Michael L. Cain, Steven A. Wasserman, Peter V. Minorsky, Jane B. Reece, Martha R. Taylor, Michael A. Pollock
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 48, Problem 2IQ
- a. What is the principal cation inside the cell? Outside the cell?
- b. Which side of the membrane has a negative charge?
- c. What change in the permeability of the cell’s membrane to K+ and/or Na+ would cause the cell’s membrane potential to shift from −70 mV to −80 mV?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Fill in the diagram, your illustration should demonstrate for each phase of the AP:
1. The relative concentration of K and Na
2. The relative voltage across the membrane
3. Any movement across the membrane of K and NA
4. The three kinds of channels in the membrane, and their state (open or closed)
5. Finally, indicate on the graph of the AP which phases correspond to hyper- polarization and which phases correspond to de-
polarization
Outside
Outside
Inside
Inside
Outside
Inside
Outside
1
Outside
Inside
Inside
Please explain what the resting membrane potential is and its value. Make sure you include all structures involved in the creation and maintenance of the resting membrane potential.
Explanation addressing the question above
Membrane potential is the difference in electric potential between the interior and the exterior of a biological cell. With respect to the exterior of the cell, typical values of membrane potential range from -40 mV to -80 mV. The membrane potential has two basic functions as a battery and transmitting signals between different parts of a cell. In non-excitable cells, the membrane potential is held at a relatively stable value, called the resting potential. The resting membrane potential of a neuron is about -70 mV. At rest, there are relatively more sodium ions outside the neuron and more potassium ions inside that neuron. It is determined by concentration gradients of ions across the membrane and by membrane permeability to each type of ion. Structure and…
Choose the correct answer:
A) When the voltage gated K+ channels open K+ moves down its concentration
gradient from the ECF to inside the cell.
O B) The value for resting membrane potential is closer to the EK+ (Equilibrium
potential for K+) than the ENa+
O C) When the membrane potential is at rest the membrane is more permeable to
Na+ than it is to K+
O D) Closing of the voltage-gated Na+ channels increases the permeability of the
membrane to Na+
Chapter 48 Solutions
Study Guide for Campbell Biology
Ch. 48 - Prob. 1IQCh. 48 - a. What is the principal cation inside the cell?...Ch. 48 - The following diagram shows the changes in...Ch. 48 - Prob. 4IQCh. 48 - Prob. 5IQCh. 48 - Prob. 6IQCh. 48 - Prob. 7IQCh. 48 - Develop a flowchart or diagram or write a...Ch. 48 - Prob. 1TYKCh. 48 - Prob. 2TYK
Ch. 48 - During a neurons resting state a. there are more...Ch. 48 - Which of the following contribute(s) to the...Ch. 48 - Prob. 5TYKCh. 48 - Prob. 6TYKCh. 48 - Prob. 7TYKCh. 48 - After the rapid depolarization of an action...Ch. 48 - Nodes of Ranvier are a. gaps where Schwann cells...Ch. 48 - Prob. 10TYKCh. 48 - Signal transmission is faster in myelinated axons...Ch. 48 - Which of the following statements concerning...Ch. 48 - Prob. 13TYKCh. 48 - Prob. 14TYKCh. 48 - Prob. 15TYKCh. 48 - Prob. 16TYKCh. 48 - Prob. 17TYKCh. 48 - If the binding of a neurotransmitter to its...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.Similar questions
- Assume that a membrane permeable to Na+ but not to Cl- separates two solutions. The concentration of sodium chloride on side 1 is higher than on side 2. Which of the following ionic movements would occur? a. Na+ would move until its concentration gradient is dissipated (until the concentration of Na+ on side 2 is the same as the concentration of Na+ on side 1). b. Cl- would move down its concentration gradient from side 1 to side 2. c. A membrane potential, negative on side 1, would develop. d. A membrane potential, positive on side 1, would develop. e. None of the preceding is correct.arrow_forwardOne of the important uses of the Nernst equation is in describing the flow of ions across plasma membranes. Ions move under the influence of two forces: the concentration gradient (given in electrical units by the Nernst equation) and the electrical gradient (given by the membrane voltage). This is summarized by Ohms law: Ix=Gx(VmEx) which describes the movement of ion x across the membrane. I is the current in amperes (A); G is the conductance, a measure of the permeability of x, in Siemens (S), which is I/V;Vm is the membrane voltage; and Ex is the equilibrium potential of ion x. Not only does this equation tell how large the current is, but it also tells what direction the current is flowing. By convention, a negative value of the current represents either a positive ion entering the cell or a negative ion leaving the cell. The opposite is true of a positive value of the current. a. Using the following information, calculate the magnitude of Na [ Na+ ]0=145mM,[ Na+ ]i=15mM,Gna+=1nS,Vm=70mV b. Is Na+ entering or leaving the cell? c. Is Na+ moving with or against the concentration gradient? Is it moving with or against the electrical gradient?arrow_forwardIf a cell with the following ion concentrations had a resting membrane potential of -40mV which of the following can you conclude? Extracellular: Cl- = 110 mM, Na+ = 145 mM, K+ = 5mM. Intracellular Cl- = 20 mM, Na+ = 10 mM, K+ = 140mM a) At rest it is only permeable to potassium b) At rest it has some permeability to more than one of these ions c) At rest it is only permeable to chloride d) Rest it is not permeable to sodiumarrow_forward
- describe what the resting membrane potential of a cell is. What is the resting membrane potential of neurons (give units)? What are the two factors that generate the resting membrane potential? Think of scenarios that change the factors that generate the resting membrane potential and how that would change the overall resting membrane potential.arrow_forwardSeparately, draw a table using arrows to depict the appropriate magnitude and direction of the forces and ion fluxes at different membrane potentials for a ligand-gated channel that is equally permeable to both ion X+ and ion Y+. The equilibrium potential for ion X+ is -60 mV, and the equilibrium potential for ion Y+ is -20 mV. Which item (a, b, c, or d) best represents the forces and fluxes for a membrane potential of +20 mV? Upwards arrows means outward direction and downwards arrow means inward direction. The length of the arrow determines the magnitude.arrow_forwardSeparately, draw a table using arrows to depict the appropriate magnitude and direction of the forces and ion fluxes at different membrane potentials for a ligand-gated channel that is equally permeable to both ion X+ and ion Y+. The equilibrium potential for ion X+ is -60 mV, and the equilibrium potential for ion Y+ is -20 mV. Which item best represents the forces and fluxes for a membrane potential of -40 mV (a, b, c, or d)? Upwards arrows means outward direction and downwards arrow means inward direction. The length of the arrow determines the magnitude.arrow_forward
- Separately, draw a table using arrows to depict the appropriate magnitude and direction of the forces and ion fluxes at different membrane potentials for a ligand-gated channel that is equally permeable to both ion X+ and ion Y+. The equilibrium potential for ion X+ is -60 mV, and the equilibrium potential for ion Y+ is -20 mV. Which item best represents the forces and fluxes for a membrane potential of 0 mV?arrow_forwardDescribe the contribution of each of the following to the establishment and maintenance of membrane potential: Part A Na+K+ Pump Passive movement of K+ across the membrane Passive movement of Na+ across the membrane Part B Resting membrane potential is approximately -70mV. Explain what resting membrane potential is and what -70mV refers to.arrow_forwardSeparately, draw a table using arrows to depict the appropriate magnitude and direction of the forces and ion fluxes at different membrane potentials for a ligand-gated channel that is equally permeable to both ion X+ and ion Y+. The equilibrium potential for ion X+ is -60 mV, and the equilibrium potential for ion Y+ is -20 mV. Which item best represents the forces and fluxes for a membrane potential of -60 mV? Pick one of the four tables in the included image please for your answer.arrow_forward
- Describe the contribution of each of the following to the establishment and maintenance of membrane potential: Part A Na+K+ Pump Passive movement of K+ across the membrane Passive movement of Na+ across the membranearrow_forwardMatch the description with the statement that best describes the following statements hyperpolarization repolarization depolarization A. usually corresponds to opening of voltage-gated potassium channels B. any change in the membrane potential that moves the membrane potential to a value more positive than the resting potential (eg from -70mV to +35mV) C. any change in the membrane potential that moves the membrane potential to a value more negative than the resting potential (eg from -70mV to -85mV)arrow_forwardIf the equilibrium potential for K* is -90mV, and the charge inside the cell is -70mV, which direction will K move across the membrane assuming there is permeability (membrane leak channels) which allow it to pass?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Human Physiology: From Cells to Systems (MindTap ...BiologyISBN:9781285866932Author:Lauralee SherwoodPublisher:Cengage Learning
Human Physiology: From Cells to Systems (MindTap ...
Biology
ISBN:9781285866932
Author:Lauralee Sherwood
Publisher:Cengage Learning
The Cell Membrane; Author: The Organic Chemistry Tutor;https://www.youtube.com/watch?v=AsffT7XIXbA;License: Standard youtube license