nervous system 1.0 Flashcards
athering information
* To monitor changes occurring inside and
outside the body (changes = stimuli)
Sensory input
processing
* to process and interpret sensory input and
decide if action is needed.
Integration
response
* A response to integrated stimuli
* The response activates muscles or glands
Motor output
Central nervous system (CNS)
Brain
*Spinal cord
Peripheral nervous system (PNS)
Nerve outside the brain and spinal cord
Nerve fibers that carry information to the
central nervous system
sensory (afferent) division
Nerve fibers that carry impulses away from
the central nervous system
Motor (efferent) division
Somatic nervous system
voluntary
Autonomic nervous system
involuntary
Abundant, star-shaped cells
*Brace neurons
* Form barrier
between capillaries
and neurons
* Control the chemical
environment of
the brain (CNS)
Astrocytes
Spider-like phagocytes
* Disposal of debris
Microglia (CNS)
Line cavities of the
brain and spinal cord
* Circulate
cerebrospinal
fluid
Ependymal cells
(CNS)
Produce myelin
sheath around
nerve fibers in the
central nervous
system
Oligodendrocytes
(CNS)
Protect neuron cell bodies
Satellite cells
Form myelin sheath in the peripheral
nervous system
Schwann cells
nerve cells
*Cells specialized to transmit messages
Neurons
nucleus and metabolic
center of the cell
*Cell body
– fibers that extend from
the cell body (dendrites and axons)
Processes
conduct
impulses toward
the cell body
Dendrites
conduct
impulses away
from the cell
body
Axons
gap between adjacent
neurons
Synaptic cleft
junction between nerves
*Synapse
produce myelin
sheaths in jelly-roll
like fashion
Schwann cells
gaps in myelin
sheath along the
axon
Nodes of Ranvier
- Carry impulses from the sensory receptors
*Cutaneous sense organs
Sensory (afferent) neurons
detect stretch or tension
*Proprioceptors
*Found in neural pathways in the
central nervous system
*Connect sensory and motor
neurons
Interneurons (association
neurons)
many extensions
from the cell body
multipolar neurons
Carry impulses from the central nervous
system
Motor (efferent) neurons
one axon and one
dendrite
Bipolar neurons
ability to transmit an
impulse
Conductivity
receives
impulses from the body’s sensory
receptors
Somatic sensory area
have a short single
process leaving the cell body
Unipolar neurons
ability to respond to stimuli
Irritability
a
stimulus depolarizes the
neuron’s membrane
- Depolarization
forms
cerebrospinal fluid
choroid plexus
sends impulses
to skeletal muscles
Primary motor area
involved in our ability
to speak
Broca’s area
Sits on top of the brainstem
* Enclosed by the cerebral hemispheres
* Made of three parts
Diencephalon
Surrounds the third ventricle
* The relay station for sensory
impulses
* Transfers impulses to the correct
part of the cortex for localization
and interpretation
Thalamus
Forms the roof of the third ventricle
* Houses the pineal body (an endocrine
gland)
* Includes the choroid plexus – forms
cerebrospinal fluid
Epithalamus
Under the thalamus
* Important autonomic nervous system
center
*Helps regulate body temperature
*Controls water balance
*Regulates metabolism
Hypothalamus
Houses the pineal body
endocrine
gland
Attaches to the spinal cord
Brain Stem
Mostly composed of tracts of
nerve fibers
*Reflex centers for vision and
hearing
Midbrain
Two hemispheres with convoluted
surfaces
* Provides involuntary coordination of
body movements
Cerebellum
Medulla Oblongata Contains important control centers such as ?
- Heart rate control
*Blood pressure regulation
*Breathing
*Swallowing
*Vomiting
The bulging center part of the
brain stem
* Mostly composed of fiber tracts
* Includes nuclei involved in the
control of breathing
Pons
The lowest part of the brain stem
* Merges into the spinal cord
* Includes important fiber tracts
* Contains important control centers
Medulla Oblongata
it is Similar to blood plasma composition
* Formed by the choroid plexus
* Forms a watery cushion to protect the
brain
* Circulated in arachnoid space,
ventricles, and central canal of the
spinal cord
Cerebrospinal Fluid
Extends from the
medulla oblongata to
the region of T12
Spinal Cord
(spinal cord) Below T12 is the?
(cauda
equina) the collection of
spinal nerves
(Spinal Cord)Enlargements occur in ?
cervical and lumbar
regions
bundle of neuron fibers
Nerve
Nerves and ganglia outside the central
nervous system
Peripheral Nervous System
Groups of fibers are
bound into fascicles
by?
perineurium
Neuron fibers are bundled by ?
connective tissue
both sensory and
motor fibers called?
Mixed nerves
Fascicles are bound
together by?
epineurium
Endoneurium
surrounds each?
fiber
carry
impulses away from the CNS
Efferent (motor) nerves
carry
impulses toward the CNS
Afferent (sensory) nerves
Cranial nerves transmit and relay information to
the brain analogous to the spinal nerves, except
they do so by direct connections to the brain
instead of the spinal cord.
TRUE OR FALSE?
TRUE
Sensory FOR?
sensation
Somatic Motor?
movement
Parasympathetic FOR?
regulation
There is a pair of spinal nerves at
the level of each vertebrae.
TRUE OR FALSE?
TRUE
The involuntary branch of the nervous
system
Consists of only motor nerves
Autonomic Nervous System
Surface lobes of the cerebrum are called?
*Frontal lobe
*Parietal lobe
*Occipital lobe
*Temporal lobe
Autonomic Nervous System IS Divided into two divisions are called?
*Sympathetic division
*Parasympathetic division
(“fight-or-flight”)
* Response to unusual stimulus
*Takes over to increase activities
* Remember as the “E” division = exercise,
excitement, emergency, and
embarrassment
Sympathetic
(housekeeping activities)
* Conserves energy
* Maintains daily necessary body functions
* Remember as the “D” division - digestion,
defecation, and diuresis
Parasympathetic
Remember as the “E” division means
exercise,
excitement, emergency, and
embarrassment
CNS stand for?
Central Nervous System
Regions of the Brain are?
- Cerebral
hemispheres - Diencephalon
- Brain stem
- Cerebellum
how chambers within the brain
Four
Remember as the “D” division means
digestion,
defecation, and diuresis
Most brain tumors involve the neurons cells,
not the neuroglia cells.
TRUE OR FALSE?
FALSE (CORRECTION- Most brain tumors involve the neuroglia cells,
not the neurons)
The sodium-potassium pump restores
the original configuration
*This action requires_______?
ATP
sodium ions rush out of the neuron
after Potassium ions rush in, which
repolarizes the membrane
FALSE (CORRECTION - Potassium ions rush out of the neuron
after sodium ions rush in, which
repolarizes the membrane)
If the action potential (nerve impulse)
starts, it is propagated over the entire
axon.
TRUE OR FALSE?
TRUE
Most brain tumors are?
gliomas