Nervous system Flashcards
Function of the Nervous system
Sensory input–gathering information
Integration—to process and interpret sensory input and decide if action is needed
Motor output—a response to integrate stimuli(activates muscles and glands)
Neurons
nerve cells
specialized to transmit messages
Two major anatomical division of the nervous system
Central Nervous System (CNS)
Peripheral Nervous System (PNS)
Central Nervous System (CNS)
Includes the brain and spinal cord
Goes through the integration process, decides if action needs to be taken against the stimuli.
Peripheral Nervous System
Nerves outside the brain and spinal cord
activate the motor neurons so that we can make a response against the neurons.
Neuroglia
support cells
abundant and star-shaped
brace neurons
form barriers between capillaries and neurons
control the chemical environment of the CNS
Motor(efferent)
Nerve fibers that carry impulses away from the central nervous system.
Part of the PNS
Has two subdivisions
Sensory(afferent division)
Nerve fibers that carry information to the Central nervous system
Part of the PNS
Somatic Nervous system
One subdivision of the motor division
under voluntary control
Autonomic Nervous system
one subdivision of the motor division
under involuntary control
Threshold Stimulus
The point that must be reached in order to initiate an action potential
Steps to Action potential
Neuron membrane maintains resting potential
threshold stimulus is received
sodium channels open up and sodium ions diffuse inward, depolarizing the membrane
potassium channels open and potassium ions diffuse outwards, repolarizing the membrane
Structure of a synapse
a presynaptic and postsynaptic terminal. The presynaptic terminal is at the end of an axon and is the place where the electrical signal (the action potential) is converted into a chemical signal (neurotransmitter release).
Axon
the elongated portion of the neuron located in the center of the cell
carries information to the receiving neuron.
