Ch 34 Vocab Flashcards
Axon hillock
Part of the neuron body that connects to he axon
Afferent
Sensory
Cell body/soma
Cell body of a neuron
Dendrites
Part of the neuron that receives impulses
Efferent neuron
Nerve impulses going away from the spinal cord
Axon terminal
Where axons make contact with other nerve cells
Glial cell
Surrounds neurons and provide support and insulation between them
Interneuron
Neuron that forms a connection between other neurons
Motor neuron
Nerve cell located in the spinal cord whose axon projects outside the spinal cord to control muscles
Myelin
Forms a layer around the axon
Nerve
Conveys impulses of sensation, motion, etc
Neuron
Building block of the nervous system
Postsynaptic cell
Recieves information from a neuron at the synapse
Presynaptic neuron
Transmits information to another cells at synapse
Schwann cells
Produce myelin sheath
Sensory neuron
Nerve cells that transmit sensory info
Synapse
Passing of signal from one nerve cell to another
Action potential
An impulse in a neuron taking the form of a wave of depolarization or hyperpolarization
All-or-nothing
Strength of a nerve is either all or nothing
Chemically gated
A channel that opens or closes depending on the presence or absence of a specific moelcule
Depolarized
Sudden electrical change
Electrochemical gradient
The concentration gradient of an ion across a membrane plus the voltage difference
Gated ion channels
Gating the flow of ions across the cell membrane
Mechanically gated
Channel that opens of closes due to mechanical force
Membrane potential
The difference in electrical charge between inside and outside of a cell
Nodes of Ranvier
Gap in the myelin sheath; the point where the axonal membrane can fire action potentials
Resting potential
Membrane potential of a cell at rest
Saltatory conduction
Action potentials jump between nodes of Ranvier
Threshold
The level of depolarization that causes an electrically excitable membrane to fire an action potential
Voltage gated
Channel that opens or closes with voltage changes
Acetylcholine (ACh)
Neurotransmitter
Excitatory
Input from a neuron that causes depolarization of the recipient cell
Inhibitory
Input from a neuron that causes hyperpolarization
Motor end plate
The depression in the postsynaptic membrane of the neuromuscular junction
Neuromuscular junction
Connects the nervous system to the muscular system via synapses
Summation
Determines whether or not an action potential will be triggered
Autonomic nervous system
Involuntary nervous system
Brainstem
Between the brain and spinal cord
Central nervous sytem
The portion of the nervous system that is the site of most information processing, storage, and retrieval
Cerebral cortex
Layer of neural tissue that overlies the cerbrum
Cerebrum
Largest part of the brain; the chief coordination center of the nervous system
Diencephalon
The portion of the forebrain that develops into the thalamus and hypothalamus
Frontal lobe
Largest brain lobe; involved with feeling and planning
Hypothalamus
Coordinates water balance, reproduction, temperature, and metabolism
Limbic system
Involved in emotions, drives, instinctive behaviors, learning, and memory
Occipital lobe
Processes visual info
Parasympathetic nervous system
Regulates body’s unconscious actions
Parietal lobe
Processes complex stimuli
Peripheral nervous system
Transmits info to and from the central nervous system
Spinal reflex
Conversion of afferent to efferent information
Sympathetic nervous system
Division of autonomic nervous system, fight-or-flight response, homeostasis
Temporal lobe
Processes auditory and visual information; involved in recognizing, identifying, and naming objects
Thalamus
Involved in integration of sensory input
