Exam 2 Flashcards
Function of the ependymal cells?
serves as a shock-absorbing fluid to prevent the brain from bumping against hard skull
Help form and circulate cerebrospinal fluid
Ependymal cells
What is blood-brain barrier?
Limit access of blood-borne materials into brain tissue
Hormonal Communications by chemical messengers
Endocrine System
Neural communication by nerve cells
Nervous system
Receptor
Response to stimulus
Sensory neuron
transmits afferent impulses to the CNS
Integration center
Region within the CNS, sensory impulse to motor impulse
motor neuron
conducts efferent impulses from integration center to effector
effector
muscle fibers and glands
somatic
carries sensory info from skin, skeletal muscles
visceral
carries sensory info from smooth muscles, glands, and organs
dorsal
upper side or back of
ventral
underside
What is salutatory conduction?
type of nerve impulse that helps signals get from one place to another
Thalamus
Motor control
receives auditory
visual signal
controls sleep and awake states
Hypothalamus
controls body temp
controls food intake
controls anterior pituitary hormone secretion
participates in sleep-wake cycle
Insula (Insular cortex)
Integrates autonomic info
Cerebellum
maintains proper position of body
motor activity
sends input to the motor areas of cortex
pons
helps regulate rate & depth of breathing
relays nerve impulses
medulla
conducts ascending and descending impulses between brain & spinal cord
contains cardiac vasomotor & resp. control center
sensory cortex
conscious awareness of sensation
motor cortex
control voluntary movement
Wernicke’s area
region of brain where spoke language is understood
language comprehension
language recognition
Broca’s area
controls speaking ability
brain stem
controls many life-sustaining processes
oldest region in brain
sympathetic
response
parasympathetic
energy
lipid soluble
bind to cytoplasmic receptors & transported to the nucleus
moves through plasma membrane
lipid insoluble
bind to cell surface receptors
binding can lead to a second messenger
Short term memory
lasts for seconds to hours
long term memory
retained for days to years
stored and can be recalled throughout a lifetime
Alzheimers disease
progressive degeneration disease of brain that results in dementia
Parkinson’s disease
degeneration of the dopamine-releasing neurons of the substatantia nigra
Huntington disease
fatal hereditary disorder caused by protein huntington that leads to degeneration of the basal nuclei & cerebral cortex
Cerebrovascular accidents
blood circulation is blocked & brain tissue dies
Transient Ischemic Attack (TIA)
blood flows to a part of brain and stops for a brief period of time
automic nerve damage
visual auditory (hearing)
motor nerve damage
muscle coordination
sensory nerve damage
emotion
Sensory & Visceral Stimuli
Afferent
Somatic & Autonomic
Efferent
Sympathetic & Parasympathetic
Autonomic
Motor neurons -> skeletal muscles
Somatic
Smooth, cardiac, exocrine, glands
Sympathetic & Parasympathetic
digestive organs only
enteric
What is EEG?
records electrical activity that accompanies brain function
Nonrapid eye movement
slow wave
rapid eye movement
paradoxical
REM
(Paradoxical)
skeletal muscles are actively inhibited
most dreaming occurs
NREM stage 1
(Paradoxical)
relaxation begins
arousal is easy
NREM stage 2
(Slow wave)
irregular EEG with sleep spindles
arousal is difficult
NREM stage 3
(Slow wave)
sleep deepens
vital signs decline
NREM stage 4
(slow wave) EEG is dominated by delta waves bed wetting night terrors sleepwalking
Synapse
small gap at the end of a neuron that allows info to pass from one neuron to the next
Presynaptic
conducts impulses toward the synapse
Postsynaptic
transmits impulses away from the synapse
Dendrite
receptive region
cell body
biosynthetic center & receptive region
axon
nerver fiber
elongated tubular extension that conducts action potential away from the
axon hillock
first portion of axon
axon terminal
release chemical messengers that influence other cells with which they come close associated
myelin sheath
reduces a membranes ion permeability
Dura mater
thickest outer layer
protective layer
supports the large venous channels that carry bloom from brain to heart
arachnoid mater
middle, thin membrane
composed of fibrous tissue
covered by flat cells
pia mater
Inner, thin membrane
surface of brain & spinal cord
astrocytes
most abudant
holds neurons together
guides neurons during fatal brain development
takes up excess K+ from brain
oligodendrogytes
enhances velocity of electrical transmission
microglia
immune defense
release low levels of growth factors in resting state
regulates mitosis, phagocyte
ependymal cells
ciliated
help form & circulate cerebrospinal fluid
ligand-gated
open with binding of a specific neurotransmitter
voltage-gated channel
open and close in response to changes in membrane potential
membrane channels
open and close in response to physical deformation of receptors
nociception
from nerve endings sensitive to temp
chemoreceptors
detect ions & molecules (smell & taste)
mechanoreceptors
changes in pressure, position, stretch, touch, hearing
thermoreceptors
hot or cold temps
pain receptors
severe heat & pressure & chemical release by inflamed tissue
What is a weak stimulus?
cause few neurons to fire and at a slow rate
What is a strong stimulus?
cause thousands of neurons to fire at the same time and at hundreds of times per second
What is the functional unit of the nervous system?
Neurons
