Podcast
Questions and Answers
Spinal nerves are part of the __ nervous system.
Spinal nerves are part of the __ nervous system.
peripheral
How many pairs of spinal nerves are there?
How many pairs of spinal nerves are there?
31
Most spinal nerves exit through __.
Most spinal nerves exit through __.
intervertebral foramen
Identify the spinal cord levels for the cervical plexus.
Identify the spinal cord levels for the cervical plexus.
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Identify the spinal cord levels for the brachial plexus.
Identify the spinal cord levels for the brachial plexus.
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Identify the spinal cord levels for the lumbar plexus.
Identify the spinal cord levels for the lumbar plexus.
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Identify the spinal cord levels for the sacral plexus.
Identify the spinal cord levels for the sacral plexus.
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Nerve plexuses contain __ rami.
Nerve plexuses contain __ rami.
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Spinal nerves contain what type of axons?
Spinal nerves contain what type of axons?
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The plexus that supplies sensory and motor nerves to the upper extremities is called?
The plexus that supplies sensory and motor nerves to the upper extremities is called?
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An individual muscle receives innervation from more than one spinal cord level.
An individual muscle receives innervation from more than one spinal cord level.
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Most branches of the cervical plexus are (motor/sensory).
Most branches of the cervical plexus are (motor/sensory).
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The most important nerve of the cervical plexus is?
The most important nerve of the cervical plexus is?
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The phrenic nerve contains fibers from spinal cord levels __ and innervates the __.
The phrenic nerve contains fibers from spinal cord levels __ and innervates the __.
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What is the sequence for the parts of the brachial plexus?
What is the sequence for the parts of the brachial plexus?
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The five major nerves of the brachial plexus that supply innervation to the arm, forearm, and hand are?
The five major nerves of the brachial plexus that supply innervation to the arm, forearm, and hand are?
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Motor innervation to the deltoid muscle is from the __ nerve.
Motor innervation to the deltoid muscle is from the __ nerve.
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Motor innervation to the biceps brachii muscle is from the __ nerve.
Motor innervation to the biceps brachii muscle is from the __ nerve.
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Motor innervation to the extensor muscles of the arm is from the __ nerve.
Motor innervation to the extensor muscles of the arm is from the __ nerve.
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The largest nerve of the brachial plexus is?
The largest nerve of the brachial plexus is?
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Motor innervation to most of the intrinsic muscles of the hand is from the __ nerve.
Motor innervation to most of the intrinsic muscles of the hand is from the __ nerve.
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The largest branch of the lumbar plexus is the __ nerve, which innervates the __.
The largest branch of the lumbar plexus is the __ nerve, which innervates the __.
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The sciatic nerve terminates in the lower leg as the __ and __ nerves.
The sciatic nerve terminates in the lower leg as the __ and __ nerves.
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Which plexus supplies the anterolateral abdominal wall, external genitals, and part of the lower extremity?
Which plexus supplies the anterolateral abdominal wall, external genitals, and part of the lower extremity?
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Which plexus supplies skin and muscles of the head, neck, and superior part of shoulders and chest?
Which plexus supplies skin and muscles of the head, neck, and superior part of shoulders and chest?
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Which plexus supplies the buttocks, perineum, and lower extremities?
Which plexus supplies the buttocks, perineum, and lower extremities?
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The sciatic nerve is a part of what plexus?
The sciatic nerve is a part of what plexus?
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The area of the skin that provides sensory input to the CNS via one pair of spinal nerves is called?
The area of the skin that provides sensory input to the CNS via one pair of spinal nerves is called?
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The levels of spinal cord that contribute to the innervation of skeletal muscles are called?
The levels of spinal cord that contribute to the innervation of skeletal muscles are called?
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C5 is involved in the __ nerve to the biceps, the __ reflex, and the __ nerve to the lateral arm.
C5 is involved in the __ nerve to the biceps, the __ reflex, and the __ nerve to the lateral arm.
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Study Notes
Overview of Spinal Nerves
- Spinal nerves are part of the peripheral nervous system.
- There are 31 pairs of spinal nerves: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal.
- Most spinal nerves exit through intervertebral foramen.
Plexuses and Their Levels
- Cervical Plexus: Spinal cord levels C1-C5.
- Brachial Plexus: Spinal cord levels C5-T1.
- Lumbar Plexus: Spinal cord levels L1-L4/5.
- Sacral Plexus: Spinal cord levels L4-S3.
Nerve Plexus Structure
- Nerve plexuses contain ventral rami.
- Each spinal nerve contains motor, sensory, and autonomic axons.
Functions and Major Nerves
- The brachial plexus supplies sensory and motor nerves to the upper extremities.
- An individual muscle receives innervation from more than one spinal cord level, emphasizing the importance of nerve redundancy.
- Most branches of the cervical plexus are sensory.
- The phrenic nerve, arising from C3-C5, innervates the diaphragm.
Brachial Plexus Structure
- Sequence of parts: Roots, Trunks, Divisions, Cords.
- Five major nerves of the brachial plexus include:
- Axillary nerve (deltoid muscle innervation),
- Musculocutaneous nerve (biceps brachii muscle innervation),
- Radial nerve (extensor muscles of the arm),
- Ulnar nerve (intrinsic muscles of the hand),
- Median nerve.
Lumbar and Sacral Plexus
- The largest nerve of the lumbar plexus is the femoral nerve, which innervates the quadriceps muscle.
- The sciatic nerve, originating from the sacral plexus, splits into the tibial and fibular nerves in the lower leg.
- The lumbar plexus innervates the anterolateral abdominal wall, external genitals, and part of the lower extremity.
- The cervical plexus supplies the skin and muscles of the head, neck, and upper chest area.
- The sacral plexus innervates the buttocks, perineum, and lower extremities.
Sensory Input Regions
- Dermatomes refer to areas of skin providing sensory input to the central nervous system via one pair of spinal nerves.
- Myotomes represent muscle groups innervated by specific spinal cord levels.
Specific Nerve Functions
- C5 contributes to:
- Musculocutaneous nerve innervating the biceps,
- The biceps reflex,
- Axillary nerve innervation to the lateral arm.
- The radial nerve is the largest branch of the brachial plexus.
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Description
Test your knowledge on spinal nerves and nerve plexuses with these flashcards. This quiz covers the basic anatomy of spinal nerves, their distribution, and the specific plexuses they form. Perfect for students of anatomy and neuroscience.
