Peripheral Nervous system Flashcards
_____- White matter of the PNs contains bundles of axons enclosed in connective tissue wrappings.
Nerve
What are the sturcture of nerves?
Endoneurium
Perineurium
Epineurium
What type of structure of nerve is this?
_____-surrounds individual axons
Endoneurium
What type of structure of nerve is this?
_____-surrounds bundles of axons called fascicles
Perineurium
What type of structure of nerve is this?
_____-surrounds entire nerve
Epineurium
How many pairs of nerves cranial nerves that carry information in out of the brain are there?
12 pairs
What type of cranial nerve is this?
_____-(CNI): sensory- carries the sense of smell (olfaction).
*Foramen (F): cribriform foramina
Olfactory nerve
What type of cranial nerve is this?
_____-(CNII): sensory- carries the sense of vision
* F: optic canal
Optic nerve
What type of cranial nerve is this?
_____-(CNIII): motor- excites most extraocular muscles (including medial rectus, superior rectus, inferior rectus, and inferior oblique), excites levator palpebrae superioris, carries parasympathetic efferent fibers that stimulate intraocular muscles (ciliary muscles, and circular pupillary constrictor muscles of the iris).
* F: superior orbital fissure
Oculomotor nerve
What type of cranial nerve is this?
_____- (CNIV): motor- excites the superior oblique extraocular muscles
F: Superior Orbital Fissure
Trochlear nerve
What type of cranial nerve is this? \_\_\_\_\_-(CNV): both sensory and motor- carries the sense of touch from the face and excites the muscles of mastication including the masseter and temporalis Three major braches of: *Opthalmic branch of trigeminal nerve *Maxillary branch of trigeminal nerve *Mandibular branch of trigeminal nerve .
Trigeminal nerve
What are the three branches of the trigeminal nerve?
- Opthalmic branch of trigeminal nerve
- Maxillary branch of trigeminal nerve
- Mandibular branch of trigeminal nerve .
What type of branches of the trigeminal nerve is this?
_____- sensory from superior facial region including ortbits,
F: superior orbital fissure
Opthalmic branch of trigeminal nerve
What type of branches of the trigeminal nerve is this?
_____-sensory from middle facial skin including superior oral region
F: foramen rotundum
Maxillary branch of trigeminal nerve
What type of branches of the trigeminal nerve is this?
_____-motor to masseter and temporalis
F: foramen ovale
Mandibular branch of trigeminal nerve .
What type of cranial nerve is this?
_____- CNVI): motor-lateral rectus extraocular muscles
F: Superior Orbital Fissure
Abducens nerve
What type of cranial nerve is this?
_____-(CNVII): both sensory and motor- carries the sense of taste from the anterior 2/3 of the tonuge and excites the muscles of facial expression including frontalis, orbicularis oris, orbicularis oculi, depressor anguli oris, depressor labii inferioris, carries parasympathetic efferent fibers that stimulate the lacrimal gland, sublingual salivary gland and submandibular salivary gland.
F: Internal Acoustic Meatus and Stylomastoid Foramen
Facial nerve
What type of cranial nerve is this?
_____-(CNVIII): sensory- carries the sense of hearing (audition)
F: Internal acoustic meatus
Vestibulocochlear
What type of cranial nerve is this?
_____-CN IX): both sensory and motor- carries the sense of taste from the posterior 1/3 of the tongue, sense of touch from the posterior tongue and pharynx, sense of blood pressure and sense of blood gas concentrations from arterial baroreceptors and chemoreceptors located in the carotid sinus, and excites muscles of the pharynx important for swallowing, and carries parasympathetic efferent fibers that stimulate the parotid salivary gland.
F: Jugular foramen
Glossopharyngeal
What type of cranial nerve is this?
_____-CNX): both sensory and motor- sensory information from visceral organs, sense of blood pressure and gas concentrations from arterial baroreceptors and chemoreceptors in the aortic arch, carries the majority of parasympathetic efferent fibers that regulate visceral organs.
F: Jugular foramen
Vagus
What type of cranial nerve is this?
______-(CNXI): motor- excites the trapezius and deltoids.
F: Jugular foramen
Accessory
What type of cranial nerve is this?
_____- CNXII): motor- excites muscles that move the tongue including genioglossus, hyoglossus, and styloglossus.
F: Hypoglossal canal
Hypoglossal
___-gray matter in the PNS
Ganglia
_____- bulge on dorsal root, contains soma of pseudounipolar sensory neurons.
Afferent fibers travel in to the spinal cord through the dorsal root.
All Spinal Nerves Have both afferent (sensory) & efferent (motor) fibers
Dorsal root ganglia
_____-forms by the fusion of ventral and dorsal nerve roots.
Trunk of a spinal nerve
______-correlates with the numbering of the intervertebral foramen where they exit the vertebral column.
Numbering of Spinal Nerve Roots/Trunks
How many pairs of cervical spinal nerve trunks are there?
8 pairs of cervical spinal nerve trunks
Where does C1 travels?
Above atlas
Where does C2-C7 travels?
number corresponds to the vertebral bone immediately inferior to the spinal nerve trunk
Where does C8 travels?
immediately superior to T1.
How are the Thoracic, Lumbar, and sacral spinal nerve trunks numbered?
according to the vertebral bone immediately inferior to the foramen they exit through.
____-spinal nerves branch shortly after exiting out of the intervertebral foramen.
Distribution of nerves
_____-small branch that curves posteriorly and innervates the skin and muscles of the posterior regions of the body
Dorsal ramus
_____-large branch that curves anteriorly and innervates the anterior trunk and the limbs
Ventral ramus
_____- interlacing nerve network formed by several ventral rami that join together then branch again.
Plexus
____-forms from C1 – C5, innervates skin and muscles of the neck and shoulder
Cervical plexus
____-forms from ventral rami of C3-C5, excites the diaphragm
Phrenic nerve
_____-forms from C5 – T1, innervates pectoral girdle and arm
Spinal nerves trunks C5-T1 are called the ____of the brachial plexus that converge to form 3 ____ of the brachial plexus: Superior (C5- C6), Middle (C7), & Inferior (C8-T1)
Each trunk divides into 2 ____-: Anterior & Posterior divisions
These six divisions unite to form 3 cords:
lateral cord
medial cord
posterior cord
Brachial plexus
- Roots
- Trunks
- Divisons
What are the six divisions unite to form 3 cords?
lateral cord
medial cord
posterior cord
What type of the six divisions unite to form 3 cords is this?
_____-formed from anterior divisions of superior & middle trunks
lateral cord
What type of the six divisions unite to form 3 cords is this?
_____-formed by anterior division of inferior trunk
medial cord
What type of the six divisions unite to form 3 cords is this?
_____-formed by union of all 3 posterior divisions
posterior cord
Cords give rise to _____ of the brachial plexus that form the specific peripheral nerves that travel through the upper limb
Branches
_____-travels down the medial brachial and antebrachial regions innervates: Flexors of medial forearm and hand; flexor carpi ulnaris, flexor digitorum profundus
Forms from C8-T1 by way of the medial cord
Ulnar nerve
_____-travels down the anterior brachial and antebrachial regions just lateral to the ulnar nerve, innervates: Flexors of lateral forearm, and hand; flexor carpi radialis, flexor digitorum superficialis
Forms from C6-T1by way of the lateral and medial cords
Median nerve
_____-travels down the anterior of the brachial region deep to biceps brachii and superficial to brachialis, innervates: Flexor arm muscles; biceps brachii & brachialis
Forms from C5-C7 by way of the lateral cor
Musculocutaneous
_______-travels down the posterior lateral brachial and antebrachial regions, innervates: Arm and forearm extensor muscles; extensor carpi or digitorum
Forms from C5-T1 by way of the posterior cord
Radial nerve
_____-travels through axillary region, innervates: Deltoid, Teres Minor
Forms from C5-C6 by way of the posterior cord
Axillary nerve
______12 – L4, innervates lower abdomen, medial and anterior portions of the thigh
Lumbar plexus
____-travels down anterior femoral region (thigh); innervates quadriceps femoris
Forms from L2-L4
Femoral nerve
____-travels down medial femoral region, innervates adductor magnus, adductor longus
Forms from L2-L4
Obturator nerve
_____L4 – S4, innervates lateral and posterior portions of femoral and sural regions
Sacral plexus
_____-largest nerve in the body, travels down the posterior femoral region; Excites hamstrings
o Forms from L4-S3
Sciatic nerve
Sciatic nerve branches ?
There is two
Tibial nerve
and Common fibular nerve
Sciatic nerve branch
_____-innervates posterior compartment of lower leg; gastrocnemius & soleus
Tibial nerve
Sciatic nerve branch
Common fibular branches into:
__________ fibular nerve – innervates lateral compartment of leg (fibularis longus and fibularis brevis muscles)
____________ fibular nerve – innervates anterior compartment of lower leg, dorsi flexors and toe extensors; tibialis anterior, extensor digitorum longus
- *Superficial fibular nerve
* **Deep fibular nerve
Of PSN
________-Controls skeletal muscles, voluntary
Muscles must be excited or they are inactive (On or off)
One motor neuron extends from the CNS all the way to the effector muscle
Somatic nervous system
Of PSN
_____- Regulates glands, smooth and cardiac muscles, involuntary
Two neuron chain between the CNS and the effector
Preganglionic neuron - cell body lies in the CNS and axon extends to an autonomic ganglia in the PNS; myelinated
Postganglionic neuron - cell body lies in the autonomic ganglia and axon extends to effector organ; unmyelinated
Autonomic nervous system
Of PSN
Autonomic nervous system
_____-cell body lies in the CNS and axon extends to an autonomic ganglia in the PNS; myelinated
Preganglionic neuron
Of PSN
Autonomic nervous system ;
_____-cell body lies in the autonomic ganglia and axon extends to effector organ; unmyelinated
Postganglionic neuron
Of PSN
_____-fight or flight, enables body to cope rapidly when excited, frightened, or during exercise and emergency situations
increases heart rate and blood pressure
activates sweat glands
pupils dilate
liver releases glucose to meet increased energy needs
sympathetic autonomic division
Of PSN
____-rest and digest, dominant in nonstressful situations, conserves energy and directs maintenance activities such as digestion and excretion
Blood to visceral organs – increase digestive tract mobility
pupil constriction
glandular secretion - digestive
BP, HR, and respiratory rates are at low normal levels
Parasympathetic autonomic division
_____:Most visceral organs are innervated by both sympathetic and parasympathetic fibers
Both divisions counterbalance each other by continuously making adjustments
The ANS either further excites or inhibits the organs activity, not turning it on or off
Dual innervation
Anatomy of the Autonomic Nervous System :
Sympathetic division
_____ origin-preganglionic fibers emerge from thoracic and lumbar spinal nerve roots (T1-L2). Length of pre and postganglionic fibers: Short preganglionic, Long postganglionic
Thoracolumbar
Autonomic Nervous System :
Sympathetic division
Location of ganglia: ________- ganglia- lateral to bodies of thoracic and lumbar vertebrae, contains soma of “postganglionic” sympathetic motor neurons that are postsynaptic to the preganglionic sympathetic motor neurons. Sympathetic efferent fibers travel from the lateral gray horn of the spinal cord out through the ventral root, then through the white ramus connecting to the ganglion.
Paravertebral ganglia “chain ganglia”
Autonomic Nervous System :
Sympathetic division
Location of ganglia:
______ ganglia – anterior to the vertebral column
Collater ganglia “Prevertebral ganglia”
Nervous System :
Sympathetic division
Location of ganglia:
______ medulla- endocrine gland directly stimulated by preganglionic sympathetic fibers. These cells release epinephrine (adrenaline) and norepinephrine (noradrenaline) into the blood stream to function as hormones
Adrenal medulla
Anatomy of the Autonomic Nervous System:
Parasympathetic division :
__________origin – preganglionic fibers emerge from brainstem and sacral regions (through cranial nerves and sacral spinal nerves.
Length of pre and postganglionic fibers: Long preganglionic, Short postganglionic
Location of ganglia – close to target organ
*Terminal ganglia – very close to target organ
* Intramural ganglia – within the walls of the target organ
Carniosacral origin
