Below is a figure from a 2015 paper that characterizes the effect of venom from the spider Selenocosmia hainana on voltage-gated sodium channels. According to the I-V curve (current-voltage curve) in Figure panel B, what is the effect of the venom on voltage-gated sodium channels? Current is on the y-axis and voltage is on the x-axis during an action potential. The figure legend denotes the concentration of the venom being applied. A rHNTX-IV (10 μM) rHNTX-IV (100 nM) Control 5 nA 10 ms B -80 -60 V(mv) -40 -20 J -6 I (NA) -8 -10 -12 -Control -- 100 nM — 10 μM 40

Below is a figure from a 2015 paper that characterizes the effect of venom from the spider Selenocosmia hainana on voltage-gated sodium channels. According to the I-V curve (current-voltage curve) in Figure panel B, what is the effect of the venom on voltage-gated sodium channels? Current is on the y-axis and voltage is on the x-axis during an action potential. The figure legend denotes the concentration of the venom being applied. A rHNTX-IV (10 μM) rHNTX-IV (100 nM) Control 5 nA 10 ms B -80 -60 V(mv) -40 -20 J -6 I (NA) -8 -10 -12 -Control -- 100 nM — 10 μM 40

Biology: The Dynamic Science (MindTap Course List)

4th Edition

ISBN:9781305389892

Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Publisher:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter39: Information Flow And The Neuron

Section: Chapter Questions

Problem 1TYK

See similar textbooks

Similar questions

Choose two false statements and explain why? Toxin causes voltage-gated sodium channels to open at a lower voltage toxin slows down the inactivation of sodium channels toxin causes ligand-gated sodium channels to open toxin causes voltage-gated potassium channels to open faster
Dendrotoxins, produced by the mamba snakes (Dendroaspis), are inhibitors of the voltage-gated K+ channels. What phase of the action potential would this toxin affect? How would it affect ion permeability during this phase? How would ion movement be affected?
The giant squid axon has a diameter = 1mm and 1 = 13mm. Compared to a mammalian neuron with a diameter = 1 um and ^ = 0.2mm, which of the following is correct? graded potentials can generate action potentials in the mammalian axon but not in the squid axon. graded potential of similar magnitude would result in action potentials with larger amplitude in the mammalian axon graded potentials of similar magnitude would result in action potentials with larger amplitude in the squid axon graded potentials of similar magnitude would travel furthest from their point of origin in the mammalian axon graded potentials of similar magnitude would travel furthest from their point of origin in the squid axon
What happens to ion channels and flow and action potential when using toxins lidocaine and TTX? How do you predict for another toxin like TEA to change the flow of ions and action potentials?
After 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.…
The rattlesnake alerts enemies to its presence with a rattle—aset of modified scales at the tip of its tail. Describe the distinctroles of gated ion channels in initiating and moving a signalalong the nerve from the snake’s head to its tail and then fromthat nerve to the muscle that shakes the rattle
Which of the following statements best describes the features of voltage-gated K+ channels? They consist of 4 subunits, are activated at the same time as voltage-gated Na+ channels, but do not inactivate. They consist of 4 subunits, are activated by depolarisation and close slowly during the refractory period. They have 24 membrane spanning alpha helices, 4 of which have positively charged amino acids which promote a conformational change in the channel following depolarisation. They consist of 4 subunits and are open at rest which causes the resting membrane potential to be close to the K+ equilibrium potential.
• Why would one use the Goldman-Hodgkin-Katz equation? • What is the role of the Na+/K+ pump in establishing ionic concentration differences and membrane potentials across the nerve membrane? • Describe the process of depolarization of the nerve membrane.
What proteins are responsible for the decrease of membrane potential in section 3? opening of voltage gated sodium channels opening of voltage gated potassium channels potassium leak channels opening of ligand gated sodium channels Na+/ K+/atpase
In 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.
The plasma membrane of the giant squid axon becomes depolarized in response to action potential. true false
dendrotoxins, produced by the mamba snakes are inhibitors of the voltage gated k+ channel. what phase of the action potential with this toxin effect? how would it affect ion permeability during this phase howard ion movement be affected?