nervous system and neurons Flashcards
MRI
Magnetic resonance imaging
lumbar puncture
needle placed between lumbar and spinal fluid to draw and check for inflammation or bacterial infection
the nervous systems includes,
brain, spinal cord, and nerves
function of nervous system
coordinate the bodys systems by receiving and sending information and maintaining homeostasis
Nervous system sensory
recieves information
nervous system integrative
determines where information is sent
nervous system motor
responds to signals
what are the two divisions of the nervous system
central nervous system and peripheral nervous system
What does the central nervous system include
brain and spinal cord
what does the peripheral nervous sytem include
peripheral nerves through the body
how many pairs of spinal nerves
31
how many pairs of cranial nerves
12
Somatic nervous system
skeletal, voluntary
autonomic nervous system
smooth muscles, glands, involuntary
what does the peripheral system divide into
somatic and autonomic
what does the autonomic nervous system divde into
parasympathetic and sympathetic
parasympathetic nervous system
rest and digest
sympathetic nervous system
fight or flight
neuron definition
mass of nerve cells that transmit information
cell body
contains the nucleus and other cell organelles
dendrites
shorter, more numerous, recieve information
axons
single long fibers, conduct information away
chromatophilic
substance, transport sustem
myelin
insulation surrounding axons
nodes of ranvier
gaps in the insulation
microglial cells
immune function, digest debris, kill bacteria
oligodendrocytes
make myelin sheath that provides insulations for axons
astrocytes
connect blood vessels to neurons
ependymal cells
form membrances around tissues
schwann cells
also form myeline sheath, found in the PNS
MYELIN SHEATHS
insulate axons
gaps in myelin sheaths are called
nodes of ranvier
myelinated
white matter, myelinated axons
unmyelinated
grey matter
what are lesions
evidence of nerve cells damage in brain or spinal cord
nerve impulses
weak electric current like a wave
neuron membrance maintains
resting position
what does bioelectric currencts stimulate
adjacent portions of the membrane
what waves travel the length of the axon as a nerve impulse
action potential
synapse
junction between 2 communicating neurons
nerve pathway
nerve impilse travels from neuron to neuron
what completes a signal
neurotransmitter released at the gap to signal the next neuron
what are the 2 kind of neurotransmitters
excitatory and inhibitory
excitatory
increase membrance permeability, increase chance for threshold to be achieved
inhibitory
decrease membrane permeability and decrease chance for threshold to be acheive
acetycholine
stimulates muscle contraction
dopamine
mood and happiness
serotonin
sleepiness and mood
andorphins
pain reduction
agonists
molecule that has the same effect on the neuron as the original neurotransmitter, it mimics the molecule
antagonist
molecule that blocs the effect of a neurotransmitter
cocain
blocks dopamine transporters
ecstasy
acts like a SSRI
heroin
block release of GABA
amphetamines
mimic dopamine
ALS
Amyotrophic Lateral Sclerosis, progressive degeneration of nerve cells in the central nervous system
Epilepsy
seizures caused by exsessive electrical activity with in networks of neurons in the brain
Myasthenia Gravis
autoimmune disorder which antibodies destroy neuromuscular connections
how many nerve cells are present before birth
100 billion
where do new nerve cells form until the age of 2
cerebellum, prefrontal cortex, and hippocampus
where do new nerve cells form in adult years
hippocampus for learning and memory
how much does the brain weigh
3 pounds
what are the 3 major parts of the brain
cerebellum, brainstem, and cerebrum
the cerebellum recieve sensory input from where
eyes, ears, joints, muscles about positions of body parts
what does the cerebellum send impulse out to
muscles to maintain posture and balance
What is the brainstem made up of
midbrain; pons and the medulla oblongata
midbrain
involved with visual reflexes
pons location
located between the midbrain and the medulla oblongata
pons
controls certain respiratory function
medulla oblongata
contains centers that regulate heart and lung functioning, swallowing, coughing, vomiting, and sneezing
what does the brainstem regulate
function of organs
Brainstem causes what
breathing, heartbeat/pulse
what is the largest part of the brain
cerebrum
what does the cerebrum do
communicates/ coordinates or other parts of brain
what controls out higher thought process: learning, memory, language, speech, reasoning
cerebrum
4 lobes in the cerebrum
parietal, occipital, temporal, frontal
parietal function
touch of skin and movement
occipital function
sight
temporal function
hearing, intelligence/ personality, walk and talk
Left temporal name
wernickes area
function of wenickes area
understand spoken and written words
Left frontal name
broca’s area
brocas area function
speak and write
cranial nerves
12 pairs of nerves that attach directly to the brain
Cranial nerve names
olfactory, optic, oculomotor, trochlear, trigeminal, abducens, facial, vestibulocochlear, glossopharyngeal, vagus, accessory nerve, and hypoglossal
olfactory function
smell
olfactory function
smell
Optic function
vision
oculomotor function
eye muscles
trochlear function
eye muscles
trigeminal function
facial (sensory), chewing muscles
abducens function
eye muscles
facial function
taste, facial muscles
vestibulocochlear function
balance and hearing
glossopharyngeal function
taste and swallowing
vagus function
longest cranial nerve, sensory and motor neurons, has branches in the ear canal (cotton swab cough)
accessory nerve function
neck and upper back muscles
hypoglossal function
tongue (motor)
