NERVOUS SYSTEM FUCK Flashcards
the nervous system consists of the
brain, spinal cord, cranial nerves,
peripheral nerves, and sensory and motor structures of the body.
monitors internal & external environment through presence of receptors.
SENSORY
interpretation of sensory information (information processing); complex (higher order)
functions.
INTEGRATION
response to information processed through stimulation of effectors.
-muscle contraction
-glandular secretion
motor function
2 anatomical division
central and peripheral nervous system
what contains the CNS
brain and spinal cord
allows for communication in the body
Peripheral Nervous System (PNS)
(sensory input
-afferent division
motor input
-efferent division
under the motor input
> somatic nervous system.
autonomic nervous system.
- Nervous Tissue is composed of two major cell types:
Neurons and Neuroglial cells.
for processing, transfer, and storage of information
neurons
conducts action potential towards the CNS
axon of sensory
conduct impulses towards the cell body
dendrites
conduct impulses away from the cell body.
axon
conducts action potential away from the CNS
axon of motor
for support, regulation & protection of neurons.
neuroglia
contains a single relatively large and centrally located nucleus with a prominent nucleolus.
Cell Body
also calles soma
cell body
aggregates of rough ER and free ribosomes. It is the primary site of protein synthesis in neurons
Nissl (nis′l) substance
are short, often highly branched cytoplasmic extensions that are tapered from
their bases at the neuron cell body to their tips.
dendrites
is a long cell process extending from the neuron cell body.
axons
the “input” part of the neuron.
dendrites
is the part of the neuron where the axon originates, is where
nerve cells generate action potentials.
Trigger zone (axon hillock)
small extensions in dendrite surfaces where axons of other neurons form
synapses with the dendrites
Dendritic spines
The “output” part of the neuron. It is the fibers that send messages to other neurons.
axons
is the junction between a nerve cell and another cell.
synapse
is the ending of an axon in the synapse.
Presynaptic Terminal
NOTE ON DENDRITES
ROUGH SURFACE
MAY DENDRITES
HAVE RIBOSOME
NO MYELIN IN SULATION
NOTE
AXON HAS NO RIBOSOME
CAN HAVE MYELIN1
1 AXON PER CELL
SMOOT SURFACE
Neurons do not touch;
there is a gap between them called
synapse
Messages are sent across the synapses by
special chemicals called
neurotrasmitter
based on the number of processes that extend from the neuron cell body
Structural -
The use of neurotransmitters
causes an
electric current
many dendrites, one axon.
multi polar neurons
-one dendrite and one axon (each end of cell body).
Bipolar neurons
single process coming off cell body, giving rise to dendrites (at one end) & axon (making up rest of
process).
Unipolar (pseudounipolar) neurons
no anatomical clues to determine axons from dendrites. Functions unknown.
Anaxonic neurons
based on the direction in which action potentials are conducted
Functional
what is the structure of sensory neuron
unipolar
structure of motor neuron
multipolar
nerve cell located between motor and sensory neurons that shuttles
signals through CNS pathways where integration occurs.
Association (interneurons
are the most common type of neuron.
interneurons
There are four types of CNS glial cells.
- Astrocytes
- Microglia
- Oligodendrocytes
- Ependymal Cells
create supportive framework for neurons.
-create “blood-brain barrier”.
Astrocytes
monitor & regulate interstitial fluid surrounding neurons.
-secrete chemicals for embryological neuron formation.
-stimulate the formation of scar tissue secondary to CNS injury.
Astrocytes
produce, monitor & help circulate cerebrospinal fluid.
-line ventricles of brain & central canal of spinal cord
Ependymal Cells
“brain macrophages”; protects CNS from infection.
- phagocytize (eats) cellular wastes and pathogens.
microglia
form myelin sheath around axons or encloses unmyelinated sheath axons of neurons in the CNS.
- myelinated axons transmit impulses faster than unmyelinated axons.
oligodendrocytes
surround all axons of neurons in the PNS creating a neurilemma/myelin sheath around
them.
Schwann Cells (neurolemmocytes
- surround neuron cell bodies in sensory ganglia
Satellite Cells
provide support and nutrition to the neuron cell bodies
Satellite Cells
protect neurons from heavy metal poisons, such as lead and mercury, by absorbing
them and reducing their access to the neuron cell bodies
Satellite Cells
together to form nerves in the PNS & tracts/pathways in the
CNS.
axons of neurons
unmyelinated structures and will be part of
gray matter
the presence of ____ speeds up the transmission of action potentials along the axon.
myelin
mainly comprised of groups of neuron cell bodies, dendrites and synapses
gray matter
the region of gray matter within the white matter
basal nuclei
the largest part of human brain.
cerebrum
deep groove that divides the cerebrum into left and right hemispheres
Longitudinal Fissure
the “executive suite” of the nervous system, where our conscious mind is
found.
cerebral cortex
a ridge or fold between two clefts or cortical region rolls and folds upon
itself which greatly increase the surface area of the cortex
gyri
the shallower grooves between the gyri
sulci
4 lobs
frontal, temporal, parietal, occipital
note on left himisphere
numerical and scientific skills
- reasoning
- ability to use and understand sign language
- receives somatic sensory signals from and
controls muscles on right side of body.
- spoken and written language.
note on right hemisphere
space and pattern perception.
- musical and artistic awareness.
- recognition of faces and emotional content of
facial expressions.
- receives somatic sensory signals from and
controls muscles on left side of body.
- generating emotional content of language.
- generating mental images to compare spatial
relationships.
- identifying and discriminating among odors
important in voluntary motor function, motivation, aggression, the sense of
smell, and mood.
frontal lobe
the major center for the reception and evaluation of most sensory information,
such as touch, pain, temperature, balance, and taste.
parietal lobe
functions in the reception and integration of visual input and is not distinctly
separate from the other lobes.
occipital lobe
receives and evaluates input for smell and hearing and plays an important
role in memory. I
temporal lobe
more on analytical
-mathematics, speech
left hemi
for musical ability
-3D/spatial perception
right hemi
understanding language at the frontal lobe.
Wernicke’s area”
motor speech at the inferior portion of frontal lobe (for speaking language).-
broca’s area
