HUMAN PHYSIOLOGY: AN INTEG ACCESS C
8th Edition
ISBN: 9780134714837
Author: Silverthorn
Publisher: PEARSON
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Chapter 8.4, Problem 22CC
Summary Introduction
To explain: The conclusion drawn by the researchers from an experiment on synaptic transmission where the action potential did not show the usual response of the photosynaptic cell.
Introduction: Communication between two or more neurons takes place through synaptic transmissions. It is a biological process where cross-talk between neurons takes place over the synapse. Neuron before the synapse, which is called the presynaptic neuron, releases some special chemicals across the synapse. These chemicals are called neurotransmitters, and they help two or more neurons to cross-talk with each other.
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Let’s say the synapses of a neuron’s dendrites are filled with glutamate-gated channels which, when activated by glutamate, cause an excitatory postsynaptic potential (EPSP) in the neuron. In one instance, glutamate is released at all of the synapses simultaneously and this leads to an action potential in the neuron.
A) What type of summation of PSPs is this? Why?
B) List the sequence of steps that occur starting from binding of glutamate to the glutamate-gated channels at the synapses and ending with the membrane potential at the axon hillock returning to resting potential at the end of the action potential. (Include all the changes in voltage-gated channels underlying the action potential.)
Fluorescent FM dyes partition reversibly into biological membranes without penetrating through them. Suppose that you have neurons cultured in a dish, and you incubate them with an FM dye for a period of time before washing the cells with excess medium to remove the dye. a) You find that if you stimulate the neurons to trigger action potentials during incubation with the dye, the synaptic regions of the neurons remain fluorescent after the wash. Propose an explanation for this effect. b) After you have generated fluorescent synaptic regions by this procedure, suppose that you trigger further action potentials while continuing to wash with excess medium. Would you expect the synaptic regions to lose fluorescence? Explain.
Given the steps shown below, which of the following is the correct sequence for transmission at a
chemical synapse?
1. neurotransmitter binds with receptor
2. sodium ions rush into neuron's cytoplasm
3. action potential depolarizes the presynaptic membrane
4. ion channel opens to allow particular ion to enter cell
5. synaptic vesicles release neurotransmitter into the synaptic cleft
O 1, 2, 3, 4, 5
O 5, 1, 2, 4, 3
O 2, 3, 5, 4, 1
O4, 3, 1, 2, 5
O 3, 2, 5, 1, 4
Chapter 8 Solutions
HUMAN PHYSIOLOGY: AN INTEG ACCESS C
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...
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