Nervous System Flashcards
Dendrites
Small cellular processes that receive input.
Cell Body
Contains nucleus.
Axon
Long process that carries information away from the cell. Information carried in the form of nerve impulses.
Sensory Neurons (afferent)
Carry impulses from peripheral body parts to CNS.
Interneurons
Lie in the CNS. Form links between other neurons, parts of the brain, and/or spinal cord. Direct impulses to appropriate regions.
Motor Neurons (efferent)
Carry nerve impulses out of the CNS to effectors (glands and muscles).
Plexus Formation
Anterior rami of the spinal nerves will join together and/or branch out forming a network known as a plexus.
Phrenic Nerve
Branches of C3-C5. Innervates the diaphragm.
Axillary Nerve
C5, C6. Paralysis - loss of shoulder abduction, weakened shoulder external rotation.
Musculocutaneous Nerve
C5, C6. Paralysis - loss of elbow flexion, weakened supination.
Radial Nerve
C6, C7, C8, T1. Paralysis - loss of elbow, wrist, finger, and thumb extension (drop wrist).
Median Nerve
C6, C7, C8, T1. Paralysis - loss of forearm pronation, loss of thumb opposition, flexion, and abduction (ape hand).
Ulnar Nerve
C8, T1. Paralysis - loss of wrist ulnar deviation.
Cranial Nerves
12 pairs.
Where does the spinal cord end?
The cord tapers to a point and ends between L1 & L2.
