Shared Flashcard Set

Details

Cortiva - APP 121 - Q2 - Lesson 1
Cards for lesson 1 of APP 121, The Nervous System
81
Other
Undergraduate 1
01/17/2011

Additional Other Flashcards

 


 

Cards

Term
The 2 Communication Systems in the Body
Definition
Nervous System, Endocrine System
Term
Nervous System
Definition
The chief coordinating agency for all systems; uses electrical impulses to relay information; fast / immediate actions
Term
Endocrine System
Definition
The chemical communication system in the body; slower actions and results than the nervous system
Term
Structural Divisions of the Nervous System (2)
Definition
Central Nervous System (CNS), Peripheral Nervous System (PNS)
Term
Central Nervous System (CNS)
Definition
The brain and spinal cord
Term
Nuclei
Definition
A bundle of cell bodies inside the CNS
Term
Tracts
Definition
A fiber bundle located within the central nervous system (CNS); sensory (ascending) and motor (descending)
Term
Peripheral Nervous System (PNS)
Definition
The cranial and spinal nerves; 2 Divisions: Afferent & Efferent
Term
Cranial Nerve
Definition
12 pairs, which carry impulses to and from the brain
Term
Spinal Nerve
Definition
31 pairs, which carry information to and from the spinal cord
Term
Afferent
Definition
Describing something being conducted toward the center
Term
Afferent Division of the PNS
Definition
Made up of sensory neurons which conduct information to the CNS (brain and spinal cord)
Term
Efferent
Definition
Describes something being conducted away from the center
Term
Efferent Division of the PNS
Definition
Made up of motor neurons which conduct information from the CNS (brain and spinal cord); includes the Somatic Nervous System and Autonomic Nervous System
Term
Functional Divisions of the Nervous System (2)
Definition
Somatic Nervous System, Autonomic Nervous System
Term
Somatic Nervous System
Definition
Controlled voluntarily; all its effectors are skeletal muscles
Term
Autonomic Nervous System
Definition
Involuntary; its effectors control smooth muscle, cardiac muscle and glands
Term
Effector
Definition
Any tissue or organ that carries out a nervous system command
Term
Sympathetic Nervous System
Definition
Division of the ANS; stimulating, active, aware; 'fight, flight or fright', but does not necessarily indicate danger
Term
Sympathetic Nervous System: Signs
Definition
Muscle tension, muscle tenderness, ticklishness, incr. heart rate, pupil dilation
Term
Parasympathetic Nervous System
Definition
Division of the ANS; reverses the stress response ('fight or flight'); calming, accepting, allowing
Term
Parasympathetic Nervous System: Signs
Definition
Yawns, twitching, nausea, headache, smiling, slow heart rate, pupil constriction
Term
Nervous Tissue
Definition
The central and peripheral nervous system make up all of this type of tissue in the body
Term
Ganglia
Definition
Cell bodies that provide relay points and intermediary connections between different structures, such as the CNS and PNS
Term
Nerve
Definition
A fiber bundle located within the peripheral nervous system (PNS)
Term
Motor Nerve (Efferent)
Definition
Contains only motor fibers conducting impulses away from the brain
Term
Sensory Nerve (Afferent)
Definition
Contains only sensory fibers conducting impulses toward the brain
Term
Mixed Nerve
Definition
Most cranial and all spinal nerves, containing both sensory and motor fibers
Term
Endoneurium
Definition
Connective tissue around a nerve fiber
Term
Perineurium
Definition
Connective tissue around a fascicle
Term
Epineurium
Definition
Connective tissue around a whole nerve
Term
Fascicle
Definition
An organization of nerve fibers
Term
Neuron
Definition
The functional cell of the nervous system
Term
Sensory Neuron (Afferent)
Definition
Conduct impulses to the brain and spinal cord
Term
Motor Neuron (Efferent)
Definition
Conduct impulses from the CNS (brain & spinal cord) to muscles and glands.
Term
Interneuron
Definition
Relay information within the CNS (brain & spinal cord)
Term
Receptor
Definition
Dendrites; receive the stimulus that begins a neural pathway
Term
Dendrite
Definition
Neuron fibers that conduct impulses to the cell body; receptors.
Term
Cell body
Definition
The nucleus and other organelles typically found in cells.
Term
Axon
Definition
Neuron fibers that conduct impulses away from cell body.
Term
Axon Terminal
Definition
Branches at the end of an axon
Term
Synapse
Definition
The junction at which a nerve impulse is transmitted, usually from the axon of one cell to the dendrite of another cell, via neurotransmitters; includes the synaptic knob, the synaptic cleft and the receptor of the other structure.
Term
Synaptic Knob
Definition
Located at the end of an axon, this stores the neurotransmitters used to transfer an impulse from a cell to another structure
Term
Synaptic Cleft
Definition
Tiny gap between cells; an impulse must travel across this gap using neurotransmitters
Term
Neurotransmitter
Definition
A chemical, stored in the synaptic knob, which is released from a presynaptic cell to carry an impulse across the synapstic cleft to the receptor of the postsynaptic cell
Term
Presynaptic Cell
Definition
The cell that is transmitting an impulse to another cell (at the synapse)
Term
Postsynaptic Cell
Definition
The cell that is receiving an impulse from another cell (at the synapse)
Term
Acetylcholine
Definition
A neurotransmitter that functions in the ANS
Term
Epinephrine / Adrenaline
Definition
A neurotransmitter that functions in the ANS
Term
Norepinephrine / Noradrenaline
Definition
A neurotransmitter that functions in the ANS
Term
Seratonin
Definition
A neurotransmitter that functions in the ANS
Term
Neuroglia
Definition
Cells that support and protect neurons; continue to multiply throughout life
Term
Glial
Definition
Greek word meaning 'glue'
Term
Phagocyte
Definition
Cells that protect the body by ingesting foreign particles; Phago- = to eat or devour; -cyte = cell
Term
Schwann Cell
Definition
In the PNS, they produce the myelin insulation for axons; each cell covers only 1 axon
Term
Myelin
Definition
A fatty material that insulates and protects some axon fibers
Term
Neurilemma
Definition
Outermost membrane of Schwann cells; this is part of the mechanism by which some peripheral nerves repair themselves.
Term
Node
Definition
Spaces between the myelin sheath of an axon that speed impulse conduction.
Term
Oligodendrocyte
Definition
Similar in function to a Schwann Cell (insulation), this neuroglia is found in the CNS and can extend much farther to cover multiple axons
Term
White Matter
Definition
Made up of white fibers, which are myelinated (insulated) axons; found in the brain and spinal cord.
Term
Grey Matter
Definition
Non-myelinated axons (non-insulated) found in the brain and spinal cord.
Term
Neurophysiology
Definition
How a neuron conducts an impulse
Term
Nerve Impulse Conduction
Definition
The electrical changes that occur as a resting neuron is stimulated and transmits a nerve impulse (compare to an electric current through a wire)
Term
Nerve Impulse
Definition
The stimulation of a resting neuron causes depolarization and repolarization which travels along the neuron.
Term
Resting Potential / Membrane Potential
Definition
The electrical charge carried in the plasma membrane of a resting (unstimulated) neuron; see Resting State and Polarization
Term
Resting State
Definition
When the ions in a neuron are in polarization, the neuron has resting potential before a stimulus creates an action potential; at the end of an action potential sequence, the neuron returns to its resting state
Term
Polarization
Definition
At rest, the ions inside the plasma membrane are negative, the ions outside are positive; the separation creates a potential for generating energy
Term
Stimulus
Definition
Any electrical, chemical or mechanical force that can start an action potential.
Term
Ions
Definition
Electrically charged particles (negative or positive)
Term
Action Potential
Definition
A sudden change in the electrical charge on a cell membrane (+ & - ions change place) which spreads along the membrane
Term
Action Potential Sequence
Definition
Resting state, (stimulus), depolarization, repolarization, resting state.
Term
Depolarization
Definition
Action Potential, Step 1: A stimulus causes positive ions to enter the plasma membrane, raising its charge.
Term
Repolarization
Definition
Action Potential, Step 2: The electrical charge of a cell returns to its resting state - positive ions move outside the plasma membrane, negative ions inside
Term
Sodium Ions (Na+)
Definition
Relates to Action Potential Sequence: 1.) Rest (Na+ concentrated outside membrane); 2.) Depolarization (Na+ enters cell); 3.) Repolarization (Sodium-Potassium Pump activates); 4.) Rest (Na+ back to original place outside the cell)
Term
Potassium Ions (K+)
Definition
Relates to Action Potential Sequence: 1.) Rest (K+ concentrated inside membrane); 2.) Depolarization (No change in K+); 3.) Repolarization (Sodium-Potassium Pump activates); 4.) Rest (Na+ back to original place outside the cell)
Term
Sodium-Potassium Pump
Definition
During repolarization: 1.) Sodium Ions (Na+) and Potassium Ions (K+) are both concentrated inside the cell; 2.) The cell membrane allows K+ to leave the cell by diffusion (the cell is trying to balance itself; see diffusion definition); 3.) To return to it's resting state, the cell forces Na+ back out and draws K+ back in; this returns the cell to its original polarization
Term
Diffusion
Definition
Substances naturally flow from areas of high concentration to areas of low concentration
Term
Threshold Stimulus
Definition
The minimum amount of stimulus needed to cause a response (such as in a muscle)
Term
All-or-none response
Definition
If a motor neuron hits the threshold stimulus, all muscle cells will contract 100% (in the motor unit); otherwise it will not contract at all.
Term
Facilitation
Definition
The more you do something, the less stimuli needed to create the same effect
Term
Inhibition
Definition
The opposite of facilitation; something that reduces the chance that a nerve impulse will occur
Supporting users have an ad free experience!