68. Anatomy - structure and function of the nervous system Flashcards
what do nerves do
- allow us to sense our environment - sensory functions and special senses
- allow us to respond to the environment aka voluntary - skeletal muscle movement and involuntary - cardiac muscle
- reflex function
what is the split in terms of the nervous system
Central Nervous System and Peripheral Nervous System
CNS contains….
brain
spinal cord
central controller
PNS contains
all other nerve tissue not within the CNS aka
Spinal, Cranial and autonomic nerves
name the parts of a neuron
dendrites
body
axon
myelin sheath
the collective name of nerve cell bodies differs in CNS vs PNS. what are the terms
CNS- nucleus
PNS- ganglion
what are nerves
bundles of axons (nerve fibres) wrapped in connective tissue
what are the 6 modalities
- Somatic sensory function
- Somatic motor function
- Special sensory function
- Visceral afferent function
- Sympathetic function
-Parasympathetic function
Describe MOTOR and SENSORY
Motor (efferent): Action potential towards body wall, body cavity or organ
Sensory (afferent): Action potential towards brain
how many lobes of each cerebral hemisphere
4
name the 4 lobes of each cerebral hemisphere
occipital, parietal, frontal, temporal
what is the outermost layer of the brain called
Cerebral cortex
the cortex has many folds. What are the grooves called
sulci (sing. sulcus)
the cortex has many folds. What are the raised parts called
gyri (sing. gyrus)
how many cranial nerves are there
12 pairs
what is the way to remember cranial nerves
Oh Oh To Touch And Feel Very Good Velvet AH
name the three Oh Oh Ohs
- Olfactory 2.Optic 3. Oculomotor
name - To Touch And Feel
- Trochlear 5. Trigeminal 6. Abducent 7. Facial
name - Very Good Velvet
- Vestibulocochlear 9. Glossopharyngeal 10.Vagus
name the AH
11.spinal Accessory nerve 12.Hypoglossal Nerve
name the 3 cranial fossae
Anterior, Middle, Posterior
name the CN1 foraminae
cribriform plate of the ethmoid bone
name the CN2 foraminae
Optic canal
CN III, IV, V1, VI foraminae?
Superior Orbital fissure
CN V2 foraminae?
foramen rotundum
CN V3 foraminae?
foramen ovale
CN VII, VIII foraminae?
internal acoustic meatus
CN IX, X, XI foraminae?
Jugular Foramen
CN XII foraminae?
Hypoglossal canal
what is the foramen at the base of the skull connecting the spinal cord
foramen magnum
how many segments of the spinal cord
4
name the segments of the spinal cord
cervical
thoracic
lumbar
sacral/coccygeal
spinal cord is protected by what
vertebral canal
where are the 2 enlargements in the spinal cord
cervical
lumbosacral
name how many of each on the spinal cord eg C1-C? and T1-T?
8 cervical - C1-C8
12 thoracic - T1-T12
5 lumbar - L1-L5
5 sacral - S1-S5
1 coccygeal - Co
where does the spinal cord end and what is that called
L1/L2 IV disc level - CONUS MEDULLARIS
which is longer. the spinal cord or rhe vertebral column
vertebral column
lumbar and sacral spinal nerve roots have to descend in the vertebral canal to their respective intervertebral foraminae this is called
cauda equina (horse’s tail)
Spinal nerves are named according to the vertebrae ……. it
except in the cervical region, where they are named according to the vertebrae ………it
for example…
above….below
C8 spinal nerve exits between C7 and T1 vertebrae
spinal nerves supply the….
soma (body wall)
spinal nerves are located only within the….
intervertebral foramina
From the intervertebral foramina they connect with
-structures of the soma via rami
-the spinal cord via roots and rootlets
where is the only place a spinal nerve is found
in the intervertebral foramina
rootlets attach to the
spinal chord
rami attach to the
soma
sensory axons travel anteriorly or posteriorly on the roots
posteriorly
Motor axons travel anteriorly or posteriorly on the roots
anteriorly
anterior rami supplies which parts of the body
-supply the remainder of the posterior part, the lateral and the anterior parts of the strips
-supply all of the limbs
what is a dermatome
area (strip) of skin supplied by both the anterior and posterior rami of a spinal nerv
which dermatome contains the nipple
T4
which dermatome contains the umbilicus (belly button)
T10
what is a nerve plexus
A plexus is a network of intersecting nerves (intertwining of the nerve fibers of anterior rami)
what is in the somatic nervous system
- Soma includes
○ head and neck walls
○ chest walls
○ Back
○ the diaphragm
○ abdominal wall
○ pelvic wall
○ limbs- Structures
○ Skin
○ Fascia
○ skeletal muscle
○ Skeleton
○ internal lining of body
cavities
- Structures
what is proprioception
your body’s ability to know where it is in a space
Somatic Sensation - Sensations felt by body wall include:
coarse touch
fine touch
vibration
proprioception
temperature
pain
coarse touch
fine touch
vibration
proprioception are all sensed by
mechanoreceptors
temperature is sensed by
thermoreceptors
pain is sensed by
nociceptors
reflexes are
rapid
reflexes are voluntary/Involuntary
Involuntary
do reflexes exclude anything in the normal pathway?
misses out pathway to brain
what are the 2 functional subdivisions of the PNS
somatic and autonomic
what is in the autonomic nervous system
- Viscera i.e. heart, lungs, kidneys
- Glands (mucous etc)
- Smooth and cardiac muscle
- External lining of organs
- Internal organs in body cavities
i.e. chest cavity, pelvic cavity, abdominal cavity - Body wall organs
i.e. sweat glands, arrector smooth muscles, arterioles
autonomic NS senses the internal environment aka organs. Their organ sensory nerves are called
visceral afferent
what sensations are from organs to the CNS
touch, temperature and pain
what can types of pain detected by the ANS
Ischaemic and colicky
what does Ischaemic mean
when there is a reduction in blood flow to tissues.
Sudden abdominal pain or cramping, Bloody stools, Diarrhea, Nausea
what is colicky pain
Colicky pain is characterized by intermittent, cramping pain that comes and goes.
It is often associated with conditions that cause spasms in the hollow organs of the body. Sharp and intense
Visceral pain is described as
dull, achy, nauseating and poorly localised
Motor neurons in the ANS respond to changes from where
internal environment
Many internal organs have sympathetic/parasympathetic/ both nerve supply???
both
dual motor control
Both motor controls
‘Accelerator’ or ‘brake’
Sympathetic Outflow
Passes down spinal cord
Exits spinal cord with ‘………..’ spinal nerves
Travel to ‘……….’ running the length of vertebral column
Pass into ? spinal nerves
Anterior or posterior rami
To supply body wall structures
They ‘Hitch a ride’ with ………to all head and neck organs and skin
Travel via …….. to reach organs
T1-L2
Sympathetic chains
Both
arteries
splanchnic nerves
during sympathetic outflow impulses exits spinal cord with ‘………..’ spinal nerves
T1-L2
During sympathetic outflow
impulses Pass down spinal cord
Exits spinal cord with T1-L2 spinal nerves
Travel to ‘……….’ running the length of vertebral column
sympathetic chains
Sympathetic Outflow
Passes down spinal cord
Exits spinal cord with ‘T1-L2’ spinal nerves
Travel to ‘Sympathetic chains’ running the length of vertebral column
Pass into Anterior or posterior rami ? spinal nerves
both
Sympathetic Outflow
Passes down spinal cord
Exits spinal cord with ‘T1-L2 spinal nerves
Travel to ‘Sympathetic chains’ running the length of vertebral column
Pass into both Anterior and posterior rami spinal nerves
To supply body wall structures
They ‘Hitch a ride’ with arteries to all head and neck organs and skin
Travel via …….. to reach organs
splanchnic nerves
which segments of the spinal cord have lateral horns
only T1-L2
All parasympathetic axons leave the CNS via which cranial nerves
III, VII, IX & X and via sacral spinal nerves
