Modules 9-11 Flashcards
(42 cards)
Bushy fibers on the neurons that receive information and conduct it toward the cell body.
Dendrites
Nerve cells, consisting of a cell body and its branching fibers.
Neuron
Long fiber that passes the message from the neuron’s branches to other neurons or to muscles and glands.
Axon
A fatty tissue layer segmentally encasing the axons of some neurons; enables transmission speed as impulses hop from one node to the next.
Myelin Sheath
A neural impulse; a brief electrical charge that travels down an axon.
Action Potential
A period of inactivity after a neuron has fired.
Refractory Period
The level of stimulation required to trigger a neural impulse
Threshold
A neuron’s reaction of either firing or not firing.
All-or-none response
The junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron.
Synapse
Chemical messengers that cross synaptic gaps between neurons, bind to the receptor sites on the receiving neurons.
Neurotransmitters
A neurotransmitter’s reabsorption by the sending neuron.
Reuptake
Natural, opiate-like neurotransmitters linked to pain-control and pleasure
Endorphins
A molecule that, binding to a receptor site, stimulates a response.
Agonist
A molecule that, binding to a receptor site, inhibits or blocks a response.
Antagonist
The body’s electrochemical communication network, consisting of all the nerve cells of the peripheral and central systems.
Nervous system
Central Nervous System
brain and spinal cord
The sensory and motor neurons that connect the central nervous system to the rest of the body.
Peripheral Nervous System
Bundled axons that form neural ‘cables’ connecting the central nervous system with muscles, glands, and sense organs
Nerves
Neurons that carry incoming information from the sensory receptors to the brain and spinal cord.
Sensory Neurons
Neurons that carry outgoing information from the brain and spinal cord to the muscles and glands.
Motor Neurons
Neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs
Interneurons
The division of the peripheral nervous system that controls the body’s skeletal muscles.
Somatic Nervous System
The part of the peripheral nervous system that controls the glands and the muscles of the internal organs.
Autonomic Nervous System
The division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations.
Sympathetic Nervous System