nervous system Flashcards
the nervous system is responsible for__________ and ________
co ordination of movement and response to environmental stimuli
what are neurons
nerve cells that specialize to carry nerve impulses
two major divisions of the nervous system
central nervous system and the peripheral nervous system
central nervous system
includes brain and spinal cord
peripheral nervous system
rest of the nervous system
parts of a neuron
dendrites
they have lots of surface area to pick up never impulses and conduct the impulse towards the cell body
cell body
metabolic center of the cell
metabolic reactions happen here
such as cellular respiration and protein synthesis
axon
away
conducts nerve impulses AWAY from the cell body
myelin sheath
made of lipids
wraps around the axon and cell body to insulate it
schwann cell
produces the myelin sheath
has tightly packed spirals of cell membrane that form layers of the myelin
nodes of ranvier
gaps in the myelin
axon is not insulated here
allows more rapid nerve conduction along axon
axon terminals or synaptic endings
end of the axon
vesicles containing neurotransmitters are located here
three types of neurons
sensory
motor
interneuron
sensory neuron
adifferent neuron
takes a message from a sense organ to the CNS has LONG dendrites and SHORT axon
motor neuron
edifferent neuron
takes message away from the CNS to a muscle fiber or gland
SHORT dendrites and LONG axon
interneuron
association neuron or connector neuron
completely contained within CNS
conveys “messages” between parts of the system
dendrites and axon can be long or short
parts of the brain stem
medulla oblongata
pons
midbrain
A neurotransmitter released in response to the parasympathetic nervous system
puts you in a relaxed state
Acetylcholine
the brain stem
medulla oblongata
The portion of the brain responsible for maintaining homeostasis within the body
hypothalamus
The dorsal root looks different than the ventral room due to the presence of an enlargement called the dorsal root _________
ganglion
the void running down the centre of the spinal cord
central canal
The dorsal root conducts nerve impulses _______ the spinal cord
towards
Shorter branches of a neuron which receive nerve impulses
dendrites
the _________ period Occurs when sodium and potassium ions are being returned to the resting potential consentration
refractory
during resting potential, __________ is the most common ion inside the cell
potassium
synaptic _______ Contain the neurotransmitters within the axon ends
vesicles
during resting potential, _______ Is the most common ion outside of the cell
sodium
The ventral root conducts nerve impulses ________from the spinal cord
away
Another word for sensory neuron
afferent neuron
Nerves are a bundles of individual cells called ________
neurons
One component of the central nervous system
the brain
The coded portions of the axon are called ______ cells
SCHWANN
Another word for motor neuron
efferent
The voltage inside a neuron at resting point is approximately _______
-70 m/V
axon _______ are at the end of the axon
terminals
The three protective membrane surrounding the spinal cord?
meninges
The space between the axon ends of wonder if cell and the dendrites of a neighbouring cell
synapse
The portion of the nervous system which produces the “fight or flight” response
sympathetic
The nodes of _______ are breaks between myelinated sections of the axon
ranvier
Portion of the cerebrum responsible for thinking
frontal
A portion of the cerebrum responsible for vision
occipital
A chemical that is released to transmit a nerve response from one cell to the next
Neurotransmitter
portion portion of the nervous system which is involuntary (not under your conscious control)
AUTONOMIC
after an action potential, sodium and potassium are returned to the resting potential state by the process of _________ __________
refractory period
The central part of the neuron were most activities related to the maintenance of the cell occur
cell body
The stage of action potential were sodium ions begin to move into the cell
Repolarization
A neurotransmitter released by the sympathetic nervous system to induce fight or flight response
Noradrenaline
_______ neurons carry nerve impulses away from the central nervous system
MOTOR
A type of neuron only found in the central nervous system
Interneuron
The portion of the cerebrum responsible for understanding speech
temoral
A portion of the nervous system which puts you into a more relaxed state
Parasympathetic
The stage of action potential were potassium ions begin to move out of the cell
Repolarization
a name given to the nerve impulse to pass it along a neuron
Action potential
the ______ Nervous system contains all the nerves that affect the skeletal muscles and sensory organs
Somatic
The portion of the nervous system that is not the CNS
PNS
An involuntary response which bypasses the brain
reflex
A substance which coats the axon of nerve cells
meylin
The part of the brain responsible for conscious thought
Cerebrum
The master gland
Pituitary gland
____________ Transmission occurs because of the myelinated nature of the axon
saltatoty
The part of the brain responsible for balance
Cerebellum
Component of the central nervous system
spinal cord
The love of the cerebrum responsible for hearing and smelling
temoral
_____ matter In the spinal cord contains mostly cell bodies
GRAY
______ Matter in the spinal cord contains bundles of myelinated axons
WHITE
there are 31 pairs of ______ nerves
spinal
The sodium potassium pump requires the energy molecule ___
ATP
