Module 9: Fundamentals of the Nervous System Flashcards
Afferent (sensory)
Carries impulses from receptors toward the central nervous system.
Efferent (motor)
Carries impulses away from the central nervous system to effectors.
Interneurons
Carries impulses from sensory to motor neuron within the central nervous system.
Neurons
Excitable cells that produce and transmit messages in the form of nerve impulses.
Neuroglia
Non-excitable, support cells for neutrons.
Dendrites
Receives signals from other neurons and transmit them toward the cell body.
Cell Body (soma)
The control centre for the neuron.
Axon
Generates nerve impulses and transmits them away from the nerve cell body.
Myelin Sheath
Insulating layer around a nerve finer.
Resting Membrane Potential
The charge difference across the plasma membrane (-70mV).
Depolarization
A shift in the resting membrane potential toward the positive (+30mV).
Repolarization
Movement of the membrane potential towards initial resting state.
Hyperpolarization
A change in membrane potential beyond resting to make it more negative.
Action Potential
A nerve impulse generate from a change in membrane polarity.
Refractory Period
A period of time after a response to stimulus that a neuron cannot respond to another stimulus.
