Axon hillock: Difference between revisions
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The Axon Hillock is the region from which the [[Axon|axon]] of a [[Neurone cell|neurone]] orginates<ref>(Silverthorn, Dee Unglaub. (2012) Human Physiology, 6th Edition, Glenview: Pearson Education, Inc, Page 242</ref>. It is located between the axon and the cell body. The axon hillock normally contains the trigger zone of the neurone. This is the area that must be depolarised to above threshold potential before it initiates the all-or-nothing response of an [[Action potential|action potential]]. The trigger zone is highly concentrated with voltage gated Na<sup>+</sup> channels | The Axon Hillock is the region from which the [[Axon|axon]] of a [[Neurone cell|neurone]] orginates<ref>(Silverthorn, Dee Unglaub. (2012) Human Physiology, 6th Edition, Glenview: Pearson Education, Inc, Page 242</ref>. It is located between the axon and the cell body. The axon hillock normally contains the trigger zone of the neurone. This is the area that must be depolarised to above threshold potential before it initiates the all-or-nothing response of an [[Action potential|action potential]]. The trigger zone is highly concentrated with voltage gated [[Voltage_gated_sodium_channels|Na<sup>+</sup> channels]] <ref>(Silverthorn, Dee Unglaub. (2012) Human Physiology, 6th Edition, Glenview: Pearson Education, Inc. Page 254</ref>. | ||
[[Graded potential]]s passing from the [[Dendrites|dendrites]] through the cell body must still be suprathreshold when they reach the axon hillock, in order for an action potential to be fired. If the graded potential is [[Subthreshold|subthreshold]] at the axon hillock, there will not be a resultant action potential | [[Graded potential]]s passing from the [[Dendrites|dendrites]] through the cell body must still be suprathreshold when they reach the axon hillock, in order for an action potential to be fired. If the graded potential is [[Subthreshold|subthreshold]] at the axon hillock, there will not be a resultant action potential <ref>(Silverthorn, Dee Unglaub. (2012) Human Physiology, 6th Edition, Glenview: Pearson Education, Inc. Pages 253-4</ref>.<br> | ||
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=== References === | === References === | ||
<references /> | <references /> | ||
Revision as of 11:59, 29 November 2012
The Axon Hillock is the region from which the axon of a neurone orginates[1]. It is located between the axon and the cell body. The axon hillock normally contains the trigger zone of the neurone. This is the area that must be depolarised to above threshold potential before it initiates the all-or-nothing response of an action potential. The trigger zone is highly concentrated with voltage gated Na+ channels [2].
Graded potentials passing from the dendrites through the cell body must still be suprathreshold when they reach the axon hillock, in order for an action potential to be fired. If the graded potential is subthreshold at the axon hillock, there will not be a resultant action potential [3].
References
- ↑ (Silverthorn, Dee Unglaub. (2012) Human Physiology, 6th Edition, Glenview: Pearson Education, Inc, Page 242
- ↑ (Silverthorn, Dee Unglaub. (2012) Human Physiology, 6th Edition, Glenview: Pearson Education, Inc. Page 254
- ↑ (Silverthorn, Dee Unglaub. (2012) Human Physiology, 6th Edition, Glenview: Pearson Education, Inc. Pages 253-4