Human Physiology: From Cells to Systems (MindTap Course List)
9th Edition
ISBN: 9781285866932
Author: Lauralee Sherwood
Publisher: Cengage Learning
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Textbook Question
Chapter 4, Problem 4TAHL
Assume 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.
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Photoreceptor cells form glutamatergic synapses onto bipolar cells and when photoreceptor cells are depolarized the release of glutamate into the synapse is increased. One class of bipolar cells, (called OFF bipolar cells) have excitatory glutamate receptors in their post-synaptic specialization. What happens to the membrane potential of OFF bipolar cells when photoreceptors are illuminated?
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.
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The neuron would have a resting membrane potential of zero
Chapter 4 Solutions
Human Physiology: From Cells to Systems (MindTap Course List)
Ch. 4.1 - Name the two types of excitable tissue.Ch. 4.1 - Prob. 2CYUCh. 4.1 - State the factor responsible for triggering gate...Ch. 4.2 - Prob. 1CYUCh. 4.2 - Prob. 2CYUCh. 4.2 - Prob. 3CYUCh. 4.3 - Draw and label an action potential, indicating the...Ch. 4.3 - Prob. 2CYUCh. 4.3 - Prob. 3CYUCh. 4.3 - Prob. 4CYU
Ch. 4.4 - Explain why synapses operate only in the direction...Ch. 4.4 - Prob. 2CYUCh. 4.4 - Prob. 3CYUCh. 4.4 - Prob. 4CYUCh. 4.5 - Define target cell.Ch. 4.5 - Distinguish among the four types of extracellular...Ch. 4.5 - Outline the three general means by which binding...Ch. 4.5 - Prob. 4CYUCh. 4.6 - Distinguish between cytokines and eicosanoids.Ch. 4.6 - Discuss the roles of phospholipase A2,...Ch. 4.6 - Prob. 3CYUCh. 4.7 - Prob. 1CYUCh. 4.7 - Prob. 2CYUCh. 4.7 - Prob. 3CYUCh. 4.8 - Prob. 1CYUCh. 4.8 - Prob. 2CYUCh. 4 - Conformational changes in channel proteins brought...Ch. 4 - Prob. 2RECh. 4 - Prob. 3RECh. 4 - Prob. 4RECh. 4 - Second-messenger systems ultimately bring about...Ch. 4 - Each steroidogenic organ has all the enzymes...Ch. 4 - Prob. 7RECh. 4 - Prob. 8RECh. 4 - Prob. 9RECh. 4 - Prob. 10RECh. 4 - Prob. 11RECh. 4 - Prob. 12RECh. 4 - Prob. 13RECh. 4 - A common membrane-bound intermediary between the...Ch. 4 - Prob. 15RECh. 4 - Prob. 16RECh. 4 - Prob. 17RECh. 4 - Prob. 18RECh. 4 - Define the following terms: polarization,...Ch. 4 - Prob. 2UCCh. 4 - Prob. 3UCCh. 4 - Prob. 4UCCh. 4 - Compare the four kinds of gated channels in terms...Ch. 4 - Prob. 6UCCh. 4 - Prob. 7UCCh. 4 - Prob. 8UCCh. 4 - Prob. 9UCCh. 4 - Define signal transduction.Ch. 4 - Compare the tyrosine kinase and JAK/STAT pathways.Ch. 4 - Prob. 12UCCh. 4 - Prob. 13UCCh. 4 - Describe how arachidonic acid is converted into...Ch. 4 - Prob. 15UCCh. 4 - Prob. 16UCCh. 4 - Explain how the cascading effect of hormonal...Ch. 4 - Prob. 18UCCh. 4 - Answer the following questions regarding...Ch. 4 - Prob. 2SQECh. 4 - Prob. 3SQECh. 4 - Prob. 1ACRCh. 4 - The rate at which the Na+K+ pump operates is not...Ch. 4 - Which of the following would occur if a neuron...Ch. 4 - Prob. 3TAHLCh. 4 - Assume presynaptic excitatory neuron A terminates...Ch. 4 - Prob. 5TAHL
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