The nervous system intro L4 Flashcards
Nervous system definition
The system of cells, tissues, and organs that regulate the body’s response to internal and external stimuli
what does communication happen via
Electrochemical impulses
3 broad points of nervous system
Responds quickly
Short lived
usually reversible effects
2 anatomical divisions
central nervous system
peripheral nervous system
3 physiological divisions
somatic
autonomic
enteric
What does sensory (afferent) do?
collect information from internal and external environment
2 sections sensory can be split into
Unconscious vs conscious
The unconscious sensory section can be split into;
proprioceptive
Interoceptive
what does proprioceptive mean
pick up stimuli related to position and vibration
What does interoceptive mean
Picks up stimuli from the organs
What can the sensory conscious section be split into
proprioceptive (inc kinaesthetic)
Exteroceptive
What do kinaesthetic receptors do
touch perception of shape and consistency
What are exteroceptive receptors split into
telereceptors
Somatic receptors
Telereceptors=
stimuli from afar not touching us
Somatic receptors=
exterior -> touch, temperature, pain
2 main terms of sensory
somatic afferents
Visceral afferents
What are visceral afferents
internal stimuli
second role of the sensory system
integrate, interpret & assess the collected information
Motor (efferent) role (2)
Produce an effect in response to stimuli (conscious)
regulate the internal environment in response to stimuli
What is the functional unit of the nervous system
neuron
In the CNS what is grey matter
cortex, horns, nuclei
In CNS what is white matter
Tracts
In the PNS what is ganglia
collection of cell bodies
Three types of neurons
multipolar neurons
bipolar neurons
unipolar
^mid brain anterior=
rostral
^mid brain posterior=
caudal
^mid brain superior=
dorsal
^mid brain inferior=
ventral
below mid brain anterior=
ventral
below mid brain posterior=
dorsal
below mid brain superior=
rostral
below mid brain inferior=
caudal
what are the connective tissue membranes encasing the CNS called
Meninges
First layer of meninges
Dura mater
2nd layer of meninges
arachnoid mater
3rd layer
Pia mater
Potential space between bone and dura
extradural (epidural in spine)
potential pace between the arachnoid and the dura
subdural
What is subarachnoid
actual space filled with cerebrospinal fluid between arachnoid and pia
Subpial =
potential space, really cerebral or spinal cord tissue filled
Key difference of spinal meninges
epidural space not extradural
is now an actual space
What is inside the epidural space
venus plexus
fat connective tissue
What does the internal vertebra venus plexus do
drains the vertebral column
where is grey matter found in the brain
the outside
what are mounds of grey matter called
gyri
What are grooves of grey matter called
sulci
What grey matter is isolated in the inside of the brain
basal ganglia
cerebrum=
large hemisphere overlapping on either side
cerebellum=
back of brain
telencephalon+ diencephalon=
prosencephalon
Rhombencephalon=
hind brain
cerebellum
denticulate ligaments=
elongated pia mater through the arachnoid mater
supportive function
White matter in spinal cord is?
on the outside
lateral horns are found in
thoracic and lumbar
components of the PNS (6)
cranial nerves spinal nerves/roots nerve plexuses & ganglia named nerves myotomes/ dermatomes autonomic nerves
what do plexuses do
help distribute nerves/axons
how many spinal segments
33
Plexuses components
cranial nerves
spinal nerves
nerve plexuses and root plexuses
named nerves
What does each spinal segment produce
a single spinal nerve
myotome=
area of muscle supplied by a single spinal segment
dermatome=
area of skin supplied by a single spinal segment
Are peripheral nerves normally mixed?
Yes
usually carry sensory, motor and autonomic components
