Nervous System Flashcards
Neuron - how it works
Dendrites carry impulses to cell body. Axon carries impulses away.
Types of neurons
Multipolar motor neurons.
Pseudounipolar sensory neurons.
Multipolar neurons
2+ dendrites, 1 axon. In ANS + control skeletal muscle.
Pseudounipolar neurons.
Short, double process that appears single. Part of PNS. Conduct impulses to CNS.
How neurons communicate with each other.
Thru neurotransmitters at synapses. Excite or inhibit next neuron.
Neuroglia (Major part of nervous tissue).
Support, insulate, nourish neurons. Non-excitable. 5x as many as neurons.
CNS: Central Nervous System.
Brain + spinal cord. Integrate + coordinate neuronal signals. Thinking + learning.
Gray matter and white matter.
Gray: Nerve cell bodies. White: interconnecting fiber tract systems.
Afferent fibers of the PNS (Peripheral Nervous System).
Convey neural impulses from sensory organs to CNS.
Efferent/motor fibers of PNS.
Convey neural impulses from CNS to effector organs (muscles and glands).
Sources of nerves
Cranial: foramina of cranium. Spinal: intervertebral foramina of vertebral column.
Anterior nerve root
Origin of spinal nerves
Efferent fibers twixt anterior horn of spinal cord gray matter + effector organs.
Posterior nerve root
Type of nerve root, composed of converged rootlets
Afferent fibers of spinal/DRG > sensory endings + posterior horn-spinal cord gray matter.
Neutron
Structural and functional unit of nervous system. For rapid communication.
