Term
| 2 Functions of Spinal Cord |
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Definition
1) pathway for sensory and motor impulses
2) cord and nerves responsible for reflexes (quickest reactions to stimuli) |
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Term
| Why is the spinal cord shorter than the vertebral canal? |
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Definition
| Because the growth of the vertebrae continues longer than the growth of the spinal cord |
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Term
| Name the Spinal Cord nerves |
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Definition
31 total
8 Cervical C1-C8
12 Thoracic T1-T12
5 Lumbar L1-L5
5 Sacral S1-S5
1 Coccygeal Co |
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Term
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Definition
When the receptor and effector organ of the reflex are on the same side of the spinal cord
Ex. left arm contracts to pull left hand away from stove |
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Term
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Definition
When the sensory impuses from a receptor organ cross over through the spinal cord to activate effector organs in the opposite limb
Ex. step on sharp object with left foot and contract right leg muscle to maintain balance. |
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Term
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Definition
| rapid, automatic involuntary reaction of muslces or glands to a stimulus |
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Term
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Definition
| neural wiring of a single reflex. Begins with receptors in PNS, communicates with CNS and ends at a peripheral effector (muscle or gland cell) |
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Term
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Definition
| Sensory axons synapse directly on motor neurons whose axons project to the effector. |
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Term
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Definition
more complex pathways that exhibit a number of synapses involving interneurons within the reflex arc.
Ex. withdraw your foot from painful stimulus, contraction of extensor muscles in limb enables you to maintain balance. |
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Term
| What are the nerve plexuses |
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Definition
| network of interweaving anterior rami of spinal nerves. Brain, cervical, lumbar, and sacral |
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Term
| What is the cervical plexus |
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Definition
innervates head, neck, and shoulder
Phrenic nerve - travels through thoracic cavity to innervate diaphragm. |
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Term
| What is the Sacral plexus |
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Definition
| Innvervates gluteal region, pelvis, posterior thigh and leg and foot. houses sciatic nerve - largest and longest nerve in the body. |
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Term
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Definition
| rapid, automatic involuntary reactions of muscles or glands to stimulus. 2 types monosynaptic and polysynaptic |
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Term
| What is a monosynaptic reflex |
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Definition
| sensory axon synapse directly on motor neuron whose axon projects to effector. No interneuron |
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Term
| What is a polysynaptic reflex |
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Definition
| more complex pathways that exhibit a number of synpases involving interneurons within the reflex arc. |
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