Reflex Arc
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Reflex Arc Reflex Arc • It’s a neural pathway that mediates in It’s a neural pathway that mediates in a reflex action. a reflex action. • The sensory neurons pass through the The sensory neurons pass through the spinal cord which allows reflex actions spinal cord which allows reflex actions to occur relatively quickly by to occur relatively quickly by activating spinal motor neurons without activating spinal motor neurons without the delay of steering signals through the delay of steering signals through the brain, although the brain will the brain, although the brain will receive sensory input while the reflex receive sensory input while the reflex action occurs. action occurs.
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Reflex Arc. It’s a neural pathway that mediates in a reflex action. - PowerPoint PPT Presentation
Transcript of Reflex Arc
Reflex ArcReflex Arc
• It’s a neural pathway that mediates in a It’s a neural pathway that mediates in a reflex action.reflex action.
• The sensory neurons pass through the The sensory neurons pass through the spinal cord which allows reflex actions to spinal cord which allows reflex actions to occur relatively quickly by activating occur relatively quickly by activating spinal motor neurons without the delay of spinal motor neurons without the delay of steering signals through the brain, steering signals through the brain, although the brain will receive sensory although the brain will receive sensory input while the reflex action occurs. input while the reflex action occurs.
Reflex ArcReflex Arc
• Monosynaptic-Monosynaptic- When a reflex arc consists of When a reflex arc consists of only two neurons in an animal ,one sensory only two neurons in an animal ,one sensory neuronneuron and one motor neuron. It refers to the . It refers to the presence of a single chemical synapse. In the presence of a single chemical synapse. In the case of peripheral muscle reflexes brief case of peripheral muscle reflexes brief stimulation to the muscle spindle results in stimulation to the muscle spindle results in contraction of the agonist muscle.contraction of the agonist muscle.
• Polysynaptic-Polysynaptic- Reflex pathways, one or more Reflex pathways, one or more interneurons connect afferent/sensory and interneurons connect afferent/sensory and efferent/motor signals. All but the most simple efferent/motor signals. All but the most simple reflexes are polysynaptic, allowing processing of reflexes are polysynaptic, allowing processing of polysynaptic reflexes within the spinal cord.polysynaptic reflexes within the spinal cord.
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