Human Physiology: An Integrated Approach (8th Edition)
8th Edition
ISBN: 9780134605197
Author: Dee Unglaub Silverthorn
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 8.3, Problem 14CC
The pyrethrin insecticides, derived from chrysanthemums, disable inactivation gates of Na+ channels so that the channels remain open. In neurons poisoned with pyrethrins, what happens to the membrane potential? Explain your answer.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Which of the following statements about voltage gated channels is true?
Voltage-gated sodium channels open at a higher (more positive) membrane potential than do potassium-gated channels
Voltage-gated sodium channels open at a lower (more negative) membrane potential than do potassium-gated channels
Sodium- and postassium-gated channels open at about the same membrane potential, but they have different effects because there are different numbers of the two kinds of channels in neuron cell membranes
Experimenters injected bark scorpion venom into mouse neurons and measured how many action potentials were generated after the venom was introduced.
Is it possible that the venom could be affecting the activity of a voltage-gated potassium channel?
What effect could the venom have on a voltage-gated potassium channel to produce this result?
What happens across the membrane of an electrically active cell is a dynamic process that is hard to visualize with static images or through text descriptions. View this animation (http://openstaxcollege.org/l/dynamic1) to learn more about this process. What is the difference between the driving force for Na+ and K+? And what is similar about the movement of these two ions?
Chapter 8 Solutions
Human Physiology: An Integrated Approach (8th Edition)
Ch. 8.1 - Organize the following terms describing functional...Ch. 8.2 - Where do neurohormone-secreting neurons terminate?Ch. 8.2 - What is the difference between a nerve and a...Ch. 8.2 - Draw a chain of three neurons that synapse on one...Ch. 8.2 - What is the primary function of each of the...Ch. 8.2 - Name the two glial cell types that form myelin....Ch. 8.3 - Given the values in Table 8.2, use the Nernst...Ch. 8.3 - Would a cell with a resting membrane potential of...Ch. 8.3 - Would the cell membrane depolarize or...Ch. 8.3 - Match each ions movement with the type of graded...
Ch. 8.3 - Prob. 11CCCh. 8.3 - What is the difference between conductance and...Ch. 8.3 - If you put ouabain, an inhibitor of the Na+-K+...Ch. 8.3 - The pyrethrin insecticides, derived from...Ch. 8.3 - When Na+ channel gates are resetting, is the...Ch. 8.3 - A stimulating electrode placed halfway down an...Ch. 8.3 - Place the following neurons in order of their...Ch. 8.4 - Prob. 18CCCh. 8.4 - Prob. 19CCCh. 8.4 - Prob. 20CCCh. 8.4 - Prob. 21CCCh. 8.4 - Prob. 22CCCh. 8.4 - Classify the H+-neurotransmitter exchange as...Ch. 8.4 - Prob. 24CCCh. 8.4 - Prob. 25CCCh. 8.4 - Is Na+-dependent neurotransmitter reuptake...Ch. 8.5 - In Figure 8.24e, assume the postsynaptic neuron...Ch. 8.5 - In the graphs of Figure 8.24a, b, why doesnt the...Ch. 8.5 - Prob. 29CCCh. 8.5 - Prob. 30CCCh. 8 - List the three functional classes of neurons, and...Ch. 8 - Somatic motor neurons control __________, and...Ch. 8 - Prob. 3RQCh. 8 - Prob. 4RQCh. 8 - Prob. 5RQCh. 8 - Prob. 6RQCh. 8 - Axonal transport refers to the (a) release of...Ch. 8 - Match the numbers of the appropriate...Ch. 8 - Arrange the following events in the proper...Ch. 8 - List the four major types of ion channels found in...Ch. 8 - Prob. 11RQCh. 8 - An action potential is (circle all correct...Ch. 8 - Choose from the following ions to fill in the...Ch. 8 - What is the myelin sheath?Ch. 8 - List two factors that enhance conduction speed.Ch. 8 - Prob. 16RQCh. 8 - Draw and label a graph of an action potential....Ch. 8 - Prob. 18RQCh. 8 - Prob. 19RQCh. 8 - Create a map showing the organization of the...Ch. 8 - Prob. 21RQCh. 8 - Prob. 22RQCh. 8 - Prob. 23RQCh. 8 - Prob. 24RQCh. 8 - The presence of myelin allows an axon to (choose...Ch. 8 - Define, compare, and contrast the following...Ch. 8 - Prob. 27RQCh. 8 - Prob. 28RQCh. 8 - Prob. 29RQCh. 8 - Prob. 30RQCh. 8 - An unmyelinated axon has a much greater...Ch. 8 - The GHK equation is sometimes abbreviated to...Ch. 8 - In each of the following scenarios, will an action...
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
- Acetylcholine is a neurotransmitter that, when bound to its receptor, causes the receptor to open a channel that allows the flow of Na+ ions into neurons. When the Na+ ions begin to flow into the neuron, this change in the net charge across the neuronal cell membrane often triggers Ca2+ ion channels to open. In this scenario, the acetylcholine receptor would be acting as a channel, and the Ca2+ channels would be classified as voltage-gated; leaky ligand gated; voltage-gated symporter; antiporter None of the above. ionarrow_forwardExplain the following; If a drug partly blocks a membrane’s potassium channels, how does it affect the action potential? Suppose the threshold of a neuron were the same as the neuron’s resting potential. What would happen? At what frequency would the cell produce action potentials?arrow_forwardThe graph shows a tracing of membrane potential change during the course of an action potential in a typical neuron. Predict the effect of exposure to the following neurotoxins. Briefly explain how you would expect the action potential to change in the presence of each toxin and why. A toxin produced by puffer fish which specifically binds to voltage-gated sodium channels and blocks the flow of sodium ions through the channel. A toxin found in scoprion venom which slows the closure of voltage-gated sodium channel inactivation gates. Assume that the cell is normally brought to threshold by an electrical stimulus applied to it, so that any change is due only to the presence of the toxin Precise values for voltage and duration are not important, just a general trend in how the action potential may differ from the typical trace shown is expected.arrow_forward
- The venom of many cobras contains a potent neurotoxin that binds to ligand-gated Na+ channels,causing them to open. Unlike ACh, which binds to and then rapidly unbinds from ligand-gated Na+ channels, the neurotoxin tends to remain bound to ligand-gated Na+ channels. How does this neurotoxin affect the nervous system’s ability to stimulate skeletal muscle contraction? How does it affect the ability of skeletal muscle fibers to respond to stimulation?arrow_forwardAfter discussing his case with his physician, he learned that he had probably been the victim of pufferfish poisoning. The active toxin in the tissues of this fish is a chemical called tetrodotoxin (TTX). Tetrodotoxin is in a class of chemicals known as neurotoxins because it exerts its effects on neurons. The specific action of tetrodotoxin is that it blocks voltage-gated sodium ion channels. Define the following phrases and terms associated with the signs and symptoms of Dr. Westwood’s TTX poisoning: diaphoresis motor dysfunction paresthesias cyanotic hypoventilating bradycardia gastric lavage oxygen saturation As mentioned in the case description, tetrodotoxin is a molecule that blocks voltage-gated sodium ion channels. What is a voltage-gated sodium ion channel and what is its function? When nerve cells are at rest, there is an unequal amount of positive and negative charges on either side of a nerve cell membrane. This charge difference creates an electrical potential.…arrow_forwardIn an experiment, the extracellular [Na+] surrounding a nerve cell was reduced from 145 to 45 mM. Which of the following is the most likely effect of this on action potentials? No action potentials would occur because the concentration of extracellular Na+ is too low. The membrane potential would become more negative so the threshold for action potential generation could not be reached. The nerve cell would still produce an action potential but its amplitude would be reduced and the depolarisation phase would be slower. The nerve cell would still produce an action potential but its amplitude would be reduced and the depolarization phase would be more rapid.arrow_forward
- In the introduction section the authors wrote “In general, the polarity-dependent mechanisms are recognized to cause membrane depolarization by anodal stimulation which increases cerebral excitability, or membrane hyperpolarization by cathodal stimulation leading to a decrease in neuronal excitability.” Based on this quote what affect, if any, does anodal stimulation have on ion channels?arrow_forwardImagine that scientists have just discovered a weird new marine tunicate at extreme depths of the ocean. They have a novel kind of neurotransmitter – maritonin – that binds to the “maritonin” receptor, which is permeable to negatively charged iodine ions (which are high concentration in seawater and in the extracellular fluid of this species). What do you predict would happen to the postsynaptic neuron when maritonin is released? Depolarization of the postsynaptic cell, increasing the chance of an action potential Hyperpolarization of the postsynaptic cell, decreasing the chance of an action potential Depolarization of the postsynaptic cell, decreasing the chance of an action potential Hyperpolarization of the postsynaptic cell, increasing the chance of an action potential In a central pattern generator, the pacemaker neural cells both have inhibitory inputs on each other. This is key for preventing opposing muscles from contracting at the same time (e.g., if your biceps and…arrow_forwardConsider the following three diagrams of a nerve cell membrane. They show resting potential, depolarization, and hyperpolarization. Figure out which one is which, then draw them in the order they occur in a cell that undergoes an action potential outside + Na* inside K* Na* Nat K Nat K Na potential: -80 mV outside + Na K* Na* inside Na+ K Nat Na* K+ potential: +30 mV outside Na Na Na Na* K+ inside K* Na* Kt potential: -70 mVarrow_forward
- 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…arrow_forwardName the three phases of an action potential. Describe for each the underlying molecular basis and the ion involved. Why is the term voltage-gated channel applied to Na+ channels involved in the generation of an action potential?arrow_forwardWhich of the following events correctly ranks steps in an action potential? 1. Voltage-gated sodium and potassium channels transition from closed to open states allowing sodium ions to enter and potassium ions to exit. 2. Voltage-gated sodium channels transition from open to inactivated states. 3. Ligand-gated sodium channels are triggered to open. 4. Peak potassium permeability. 5. Peak sodium permeability. 6. Membranes hyperpolarize due to more potassium ions exiting cell and neuron enters refractory period. 7. Critical threshold is achieved. O 3, 1, 7, 5, 2, 4, 6 O 3, 7, 1, 5, 4, 6, 2 O 3, 4, 1, 2, 6, 7,5 O 6, 7, 3, 2, 5, 4, 1 O 7, 5, 3, 1, 4, 6, 2 4, 6, 3, 7, 5, 2, 1arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Human Anatomy & Physiology (11th Edition)BiologyISBN:9780134580999Author:Elaine N. Marieb, Katja N. HoehnPublisher:PEARSON
Biology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStax
Anatomy & PhysiologyBiologyISBN:9781259398629Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa StouterPublisher:Mcgraw Hill Education,
Molecular Biology of the Cell (Sixth Edition)BiologyISBN:9780815344322Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter WalterPublisher:W. W. Norton & Company
Laboratory Manual For Human Anatomy & PhysiologyBiologyISBN:9781260159363Author:Martin, Terry R., Prentice-craver, CynthiaPublisher:McGraw-Hill Publishing Co.
Inquiry Into Life (16th Edition)BiologyISBN:9781260231700Author:Sylvia S. Mader, Michael WindelspechtPublisher:McGraw Hill Education
Human Anatomy & Physiology (11th Edition)
Biology
ISBN:9780134580999
Author:Elaine N. Marieb, Katja N. Hoehn
Publisher:PEARSON
Biology 2e
Biology
ISBN:9781947172517
Author:Matthew Douglas, Jung Choi, Mary Ann Clark
Publisher:OpenStax
Anatomy & Physiology
Biology
ISBN:9781259398629
Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa Stouter
Publisher:Mcgraw Hill Education,
Molecular Biology of the Cell (Sixth Edition)
Biology
ISBN:9780815344322
Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter Walter
Publisher:W. W. Norton & Company
Laboratory Manual For Human Anatomy & Physiology
Biology
ISBN:9781260159363
Author:Martin, Terry R., Prentice-craver, Cynthia
Publisher:McGraw-Hill Publishing Co.
Inquiry Into Life (16th Edition)
Biology
ISBN:9781260231700
Author:Sylvia S. Mader, Michael Windelspecht
Publisher:McGraw Hill Education
The Cell Membrane; Author: The Organic Chemistry Tutor;https://www.youtube.com/watch?v=AsffT7XIXbA;License: Standard youtube license