Ch 14 Flashcards
What are the functions of the spinal cord?
Two-way communication to brain
Reflexes
Where is the cornus medullaris located?
Inferior end of spinal cord
Where does the filum terminale attach?
Coccyx
What does cauda equina mean?
Pony tail
What is the cauda equina?
Collection of spinal nerve roots
What are the names of the two deep grooves that run the lenght of the spinal cord?
Dorsal median sulcus
Ventral median fissure
What is the white matter of the spinal cord made of?
Unlyelinated axons
What are the three types of spinal cord fibers?
Ascending
Descending
Commisural
What are the spinal cord dorsal horns composed of?
Intrernuerons
What is the organization of the gray spinal matter?
Posterior: somatic sensory, SS
Posterior: visceral sensory, VS
Anterior: visceral motor, VM
Anterior, somatic motor, SM
What protects the spinal cord?
Vertebrae
CSF
Meninges -Dura mater -Arachnoid mater -Pia mater
What does the cerebrospinal fluid do?
Cushions
Nurishes
Removes wastes
Carries chemical signals
How many pairs of spinal nerves are there?
31 pairs
What are the paris of spinal nerves numbered?
C1-C8 T1-T12 L1-L5 S1-S5 Co1
What do the dorsal and ventral spinal root fibers do?
Dorsal: sensory
Ventral: motor
What does the dorsal rami do?
Innervates the back muscles
What is the nerve plexus?
The network of nerves
What body part is primarily served by the nerve plexus?
Limbs
What are the names of the the nerve plexuses?
Cervical plexus
Brachial plexus
Lumbar plexus
Sacral plexus
What is the most important nerve of the cervical plexus?
The phrenic nerve, innervates the diaphragm
What does rami mean?
Branches
Which nerve numbers are in the brachial plexus?
C5-C8
What is the hierachry of the brachial plexus?
Roots
Trunks
Divisions
Cords
Really Tired Drink Coffee
What is the main branch of the lateral cord?
Musculocutaneous
The “Hand of Benedection” indicated what neurological problem?
Median nerve injury
“Clawhand” indicates what neurological problem?
Ulnar nerve injury
“Drop-wrist” indicates what neurological problem?
Radial posterior cord
What does the lumbar plexus innervates?
Abdominal wall
Psoas
What are the main branches of the lumbar plexus?
Femoral nerve
Obturator nerve
What are the two nerves in the sciatic nerve?
Tibial
Fibular
What does the pudenal nerve do?
Innervates the preineum
What are dermatomes?
An area of skin innervated by a single spinal nerve branch
What is the upper limb and lower limb nerves called?
Upper Limb
Brachial plexus
Lower Limb
Lumbar nerves - anterior
Sacral nerves - posterior
What are the classifications of the peripheral nervous system?
Sensory input
Motor output -somatic motor, skeletal muscle, vol/invol
Visceral motor, smooth & cardiac muscle, invol
What is the funcitonal organization of the PNS?
CNS<>PNS Sensory (Afferent) -Somatic sensory -Visceral sensory Motor (efferent) -Somatic motor -Visceral motor
What are nerves?
Bundles of axons
What are ganglia?
Clusters of neuronal cells
What are two main categories of sensory receptors?
Free nerve endings of sensory neurons
Complete epithelial receptor cells (encapusulated nerve endings)
Describe the three sensory receptor cells by location?
Exteroceptors - external stimuli Interoceptors - visceral stimuli Proprioceptors - musculoskeletal stretch
Describe the five sensory receptors by stimulus detected
Mechanorecptors - mechanical forces
Thermoreceptors - temperature changes
Chemoreceptors - chemical changes
Photoreceptors - eyes respond to light
Nocioceptors - respond to stimuli that result in pain
Free nerve endings respond to what stimulus?
In epithelia, respond to temperature and pain
What are two types of free nerve endings?
Merkel discs in epidermis
Hair follicle receptors
What are encapsulated nerve endings enclosed in?
Connective tissue
What are Ruffini’s corpuscles for?
Pressure sensing
What do proprioceptors do?
Measure muscle stretch
What do muscle spindles, joint kinesthetic and Golgi tendons do?
Measure muscle stretch
Where does the spinal cord begin and end?
It begins at the Medulla oblongata; ends at L1/L2
The inferior end of the spinal cord is secured to the coccyx by what?
Where the conus medullars (cone) meets the cauda equina
The diaphragm is innervated by what nerve?
Phernic nerve
The intercostal nerve innervates which muscle?
Intercostal muscle
In the brachial plexus, what division gives rise to the main nerves?
Cords
Describe the arrangement of:
cervical nerves to cervical discs
When we cannot judge position correctly, we may have dysfunctional ?
Propriceptors
