Human Physiology
15th Edition
ISBN: 9781259864629
Author: Fox, Stuart Ira
Publisher: Mcgraw-hill Education,
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Textbook Question
Chapter 7, Problem 40RA
Use the figure below (from figure 7.34) to answer questions 38-40:
If the IPSP had not occurred, what would be the difference between the EPSP and the threshold required to produce an action potential?
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Chapter 7 Solutions
Human Physiology
Ch. 7 - Draw a neuron, label its parts, and describe the...Ch. 7 - Distinguish between sensory neurons, motor...Ch. 7 - Describe the structure of the neurilemma, and...Ch. 7 - Explain how myelin sheaths are formed in the CNS....Ch. 7 - Explain what is meant by the blood-brain barrier....Ch. 7 - Define the terms depolarization and...Ch. 7 - Prob. 4bCPCh. 7 - Describe how gating of Na+andK+ in the axon...Ch. 7 - Prob. 5aCPCh. 7 - Prob. 5bCP
Ch. 7 - Prob. 6aCPCh. 7 - Describe the location of neurotransmitters within...Ch. 7 - Describe the sequence of events by which action...Ch. 7 - Explain how chemically regulated channels differ...Ch. 7 - Prob. 8CPCh. 7 - Prob. 9aCPCh. 7 - Prob. 9bCPCh. 7 - Prob. 10CPCh. 7 - Prob. 11CPCh. 7 - Prob. 12aCPCh. 7 - Prob. 12bCPCh. 7 - Prob. 13aCPCh. 7 - Prob. 13bCPCh. 7 - Prob. 14aCPCh. 7 - Describe the mechanism of action of glycine and...Ch. 7 - Give examples of endogenous opioid polypeptides,...Ch. 7 - Prob. 15bCPCh. 7 - Prob. 16CPCh. 7 - Prob. 17aCPCh. 7 - Prob. 17bCPCh. 7 - Prob. 17cCPCh. 7 - Prob. 1RACh. 7 - Prob. 2RACh. 7 - Prob. 3RACh. 7 - Prob. 4RACh. 7 - Repolarization of an axon during an action...Ch. 7 - As the strength of a depolarizing stimulus to an...Ch. 7 - Prob. 7RACh. 7 - Which of these is not a characteristic of synaptic...Ch. 7 - Prob. 9RACh. 7 - Prob. 10RACh. 7 - Prob. 11RACh. 7 - Prob. 12RACh. 7 - Prob. 13RACh. 7 - Prob. 14RACh. 7 - Prob. 15RACh. 7 - Prob. 16RACh. 7 - Prob. 17RACh. 7 - Which of these may be produced by the action of...Ch. 7 - Prob. 19RACh. 7 - In a step-by-step manner, explain how the...Ch. 7 - Prob. 21RACh. 7 - Prob. 22RACh. 7 - Prob. 23RACh. 7 - Prob. 24RACh. 7 - Once an EPSP is produced in a dendrite, how does...Ch. 7 - Prob. 26RACh. 7 - List the endogenous opioids in the brain and...Ch. 7 - Explain what is meant by long-term potentiation...Ch. 7 - Prob. 29RACh. 7 - Prob. 30RACh. 7 - Prob. 31RACh. 7 - Prob. 32RACh. 7 - Prob. 33RACh. 7 - Explain the nature of the endocannabinoids....Ch. 7 - Prob. 35RACh. 7 - Prob. 36RACh. 7 - Prob. 37RACh. 7 - Prob. 38RACh. 7 - Prob. 39RACh. 7 - Use the figure below (from figure 7.34) to answer...
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- Explain how the binding of heroin to presynaptic neurones raises the probability of action potentials in the postsynaptic neurone. asap typed onlyarrow_forwardYou have isolated a neurotoxin from a newly discovered snake species. When you administer the toxin to brain tissue, you can no longer record an excitatory postsynaptic potential after you experimentally stimulate the presynaptic neuron. a. Draw what the experimental setup would look like. Also include a picture of the recording you would get from the postsynaptic neuron after the presynaptic stimulation before and after the administration of the toxin. Label your figures completely and label all axes.arrow_forwardWhat is the approximate magnitude of the IPSP (how many mV)?What is the approximate magnitude of the EPSP (how many mV)?If the IPSP had not occurred, what would be the difference between the EPSP and the thresholdrequired to produce an action potential?arrow_forward
- Neuron A is an inhibitory neuron that is activated when the person feels heat in the tip of their index finger. Neuron A sends signals to neuron B (the postsynaptic neuron). First consider how a stimulus impacts the firing rate of neuron A. For example, when the person touches ice with their index finger vs. when the person touches a hot cup of coffee with their index finger? How would each of these impact the frequency of action potentials, the size of action potentials and the amount of neurotransmitter released. Second, consider Drug-D that causes all sodium channels in neurons to close immediately. How would taking Drug-D affect the firing rate of neuron A when the person touches a hot pan? In turn, how would this affect the firing rate of post-synaptic neuron B? Rubric: Impact of heat on A Impact of ice on A ( Impact of drug X on A Impact of drug X on B 1arrow_forwardImagine that a toxin creates pores that are permeable to Ca2+. Describe its immediate effect on the resting potential of the neuron: identify which ions diffuse across the membrane, which direction they diffuse (and why), and whether this brings the neuron closer to or further from threshold potential. asap pleasearrow_forwardAn undisclosed drug (Drug A) is a drug that can block voltage-gated K+ channels when being introduced into the bloodstream. Explain the effects of Drug A on the action potentials produced by a neuron. If Drug A could be applied selectively to a presynaptic neuron that releases an excitatory neurotransmitter, analyse how would it alter the synaptic effect of the neurotransmitter on the presynaptic cell. Remark: The word count limit (250 words only), no less than 100 wordsarrow_forward
- A laboratory experiment is set up where you have two fully functional nerves properly aligned so that it potentially can transmit an action potential through a synapse to the second nerve. The buffer outside the cells contain Na+, H+ and Cl- as the only inorganic ions. When you stimulate the nerve, surprisingly the second nerve does not respond. What is the most likely explanation for the failure of the second nerve response? State why you chose your answer. a. The lack of K+ in the buffer prevents propagation of the action potential b. Neurotransmitter is not being released into the synaptic space. c. An action potential can only be initiated by opening a ligand-gated channel. d. Although neurotransmitter is released, it is unable to stimulate opening of the second nerve' ligand-gated channel. e. Repolarization of the axon does not occur in this buffer.arrow_forwardAssume presynaptic excitatory neuron A terminates on a postsynaptic cell near the axon hillock and presynaptic excitatory neuron B terminates on the same postsynaptic cell on a dendrite located on the side of the cell body opposite the axon hillock. Explain why rapid firing of presynaptic neuron A could bring the postsynaptic neuron to threshold through temporal summation, thus initiating an action potential, whereas firing of presynaptic neuron B at the same frequency and the same magnitude of EPSPs may not bring the postsynaptic neuron to threshold. thanks a lot in advance:)arrow_forwardBased on the graph, how soon could another action potential be easily initiated (at the end of the relative refractory period) after the first stimulus? (Base your answer to this question on the graph below depicting an action potential.) less than 0.5 msec 1 msec 2 msec 3 msec 4 msecarrow_forward
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