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1 Stepping on a tack stimulates SENSORY RECEPTOR (dendrites of pain-sensitive neuron) in right foot Withdrawal of right leg (flexor reflex)
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Crossed Extensor Reflex
Process Diagrams Step-by-Step
Copyright © 2007 by John Wiley & Sons, Inc.
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Withdrawal of right leg(flexor reflex)
Stepping on a tackstimulates SENSORYRECEPTOR (dendrites ofpain-sensitive neuron) inright foot
1
SENSORYNEURONexcited
Withdrawal of right leg(flexor reflex)
Stepping on a tackstimulates SENSORYRECEPTOR (dendrites ofpain-sensitive neuron) inright foot
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1
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Ascendinginterneurons
SENSORYNEURONexcited
Spinalnerve
Within INTEGRATING CENTER(spinal cord), sensory neuronactivates several interneurons
Descendinginterneurons
Withdrawal of right leg(flexor reflex)
Stepping on a tackstimulates SENSORYRECEPTOR (dendrites ofpain-sensitive neuron) inright foot
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2
3
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Interneuronsfrom other side
1
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Ascendinginterneurons
SENSORYNEURONexcited
Spinalnerve
Within INTEGRATING CENTER(spinal cord), sensory neuronactivates several interneurons
MOTORNEURONSexcited
Descendinginterneurons
Withdrawal of right leg(flexor reflex)
Stepping on a tackstimulates SENSORYRECEPTOR (dendrites ofpain-sensitive neuron) inright foot Extension of left leg
(crossed extensor reflex)
MOTORNEURONSexcited
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Interneuronsfrom other side
1
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Ascendinginterneurons EFFECTORS
(extensor muscles)contract, and extendleft leg
SENSORYNEURONexcited
Spinalnerve
Within INTEGRATING CENTER(spinal cord), sensory neuronactivates several interneurons
MOTORNEURONSexcited
Descendinginterneurons
Withdrawal of right leg(flexor reflex)
Flexor musclescontract and with-drawright leg
Stepping on a tackstimulates SENSORYRECEPTOR (dendrites ofpain-sensitive neuron) inright foot Extension of left leg
(crossed extensor reflex)
MOTORNEURONSexcited
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2
3
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5
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Interneuronsfrom other side
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