Q6 Nervous System Flashcards
outline the basic nervous system pathway
sensation in the environment -> sensory info in (afferent neuron) -> CNS processing -> motor information out (efferent neuron) -> response in gland, muscle or tissue
CNS consists of
spinal cord and brain
PNS consists of
everything else
Afferent division consists of what types of receptors
Somatic Sensory (info about outside world/our position in it) Visceral Sensory receptors (info about internal conditions and status of organ systems) Special sensory receptors (special senses)
Efferent division consists of
Somatic NS (somatic effectors) Autonomic NS - (visceral effectors - smooth/cardiac muscle and glands)
2 main nervous cell types and which is bigger
Nerve cells/neurons/nerve fibre (bigger)
Neuroglia/glia
2 types of glia and their functions for CNS we need to know
Astrocytes Function: 1. Maintain blood brain barrier 2. structural support 3. regulate nutrient/dissolved gas concentrations 4. absorb, recycle neurotransmitters 5. form scar tissue after injury
Oligodendrocytes
Function:
1. myelinated CNS axons
2. provide structural frame work
2 types of glia we need to know in the PNS and their functions
Schwann Cells
Function:
1. surround all axons in PNS (myelination)
2. repair after injury
Satellite Cells
Function:
1. surround neuron body in ganglia, regulate O2, CO2, nutrient and neurotransmitters levels around ganglia.
function of a neuron
transmit info in the form of electrical impulses from one part of the nervous system to another
3 functional types of neurons
sensory, motor, interneurons
four structural types of neurons and functional example of each
Anaxonic - special senses, only in CNS
Bipolar - special sensory, rare, sight, hearing, smell
Pseudo-unipolar - sensory neurons of PNS, aka “uni-polar”
Multi-Polar - most common type of neuron; all motor neurons
in PNS, neuron cells bodies clustered together in masses are called
ganglia
Neuron cellular structures, name all, make sure you can identify
Dendrites cell body or soma -nucleus Axon -axon hillock -myelin sheath -neurilemma/neurolemma -myelin sheath gaps (nodes of ranvier) -synaptic (or axon) terminals
Three types of receptors and what info they provide
- Interoreceptors (visceral) - digestive, respiratory, cardiovascular, urinary, reproductive, deep pressure/pain and taste
- Proprioreceptors (position of skeletal muscles and joints) -Exterorecpetors (somatic) touch, temp, pressure, sight, smell, hearing
muscles spindles are found where and monitor what
found in muscles and monitor length of skeletal muscles
Golgi tendon bodies found where and monitor what
found at origins/insertions.into tendons and monitor tension in muscles during contraction.
4 different sensory receptors and the type of stimuli they detect
Nociceptor (pain) Thermoreceptor (temperature) Chemoreceptor (chemical composition) Mechanoreceptors (7 types) -Fine touch -Light touch, movement, and vibration -Deep pressure and distortion -pressure and vibration -pressure -muscle length -tension
specific receptor name for/found where: nociceptors
free nerve ending for pain
skin, joint capsule, periosteum, blood vessel walls
specific receptor name for/found where:
thermorecepetor
free nerve ending for temperature
skeletal muscle, liver, skin, hypothalamus
specific receptor name for/found where: chemoreceptor
free nerve ending for chemical composition
Brain, carotid bodies, aortic bodies, skin
specific receptor name for/found where: mechanoreceptor - fine touch
exteroceptors
papillary layer of dermis, epidermis, hair follicles
specific receptor name for/found where: mechanoreceptor - light touch, movement and vibration
exteroceptors
eyelids, lips, skin, fingertips, nipples, external genitalia
specific receptor name for/found where: mechanoreceptor - deep pressure/and distortion
exteroceptors
capsule of collagen fibres of dermis
specific receptor name for/found where: mechanoreceptor - pressure and vibration
interceptor and exteroceptor
skin (fingers, treats, genitals), fascia, periosteum, urethra, urinary bladder, pancreas
specific receptor name for/found where: mechanoreceptor - pressure
interoceptors
blood vessels, lungs, urinary and digestive tracts
specific receptor name for/found where: mechanoreceptor - muscle length
proprioceptor
skeletal muscle
specific receptor name for/found where: mechanoreceptor - tension
proprioceptor
tendons of skeletal muscle
three functions of spinal meninges
protection, shock absorption, physical stability
3 meningeal layers
dura mater, arachoid mater, pia mater
type of tissue spinal dura mater is made up of and what surrounds inner and outer surfaces
dense irregular connective tissue - simple squamous epithelium
epidural space - what is in there?
areolar tissue, blood vessels, adipose tissue
at what vertebrae does the spinal cord end?
L1 or L2
what is the cauda equina and where is it found?
the filum terminal and the long ventral and dorsal roots together make it up.
found from L1 to the dorsum of the coccyx where it connects the spinal cord to the coccygeal vertebrae.
white matter in spinal cord does what and organized how?
organized into columns or “funiculi” and transmit both sensory and motor information to and from the brain
central canal of spinal cord has what flowing through?
cerebrospinal fluid
three horns present in gray matter of spinal cord
posterior, anterior, lateral (only in thoracic and superior lumbar segments)
define nerve
a bundle of axons in the PNS
how are spinal nerves named?
take name of thoracic vertebrae immediately inferior to them
how are thoracic and lumber nerves named?
nerves caudal to the first thoracic vertebrae take names from vertebrae immediately superior to them
Dorsal roots of the spinal nerve carry what
sensory/afferent input
ventral roots of the spinal nerve carry what
motor/efferent out put
what type of neurons cell bodies occupy this the Doral root ganglion?
sensory neurons
what do we need to able be able to identify on the spinal cord model
dorsal and ventral roots of the spinal nerve, dorsal root ganglion, spinal nerve, dorsal and ventral ramus of the spinal nerve, white and gray rami communicantes and sympathetic ganglia
Dorsal rami carry what?
nerves serving posterior trunk
ventral rami carry what?
nerves serving lateral and anterior areas of the trunk and entire limbs.
4 major nerve plexuses
cervical plexus
brachial plexus
lumbar plexus
sacral plexus
what does the phrenic nerve innervate?
the diaphragm, rhomboid major and minor, serrates anterior
what do nerves of the brachial plexus carry?
nerve fibers for muscles, blood vessels, sensory receptors, sweat glands and arrestor pili muscles of the upper limb.
lateral cord sends a nerve where and branch to what nerves?
nerve to pectorals major m. and a branch to the median nerve and musculocutaneous nerve
musculocutaneous nerve : muscular branch innervates? cutaneous branch innervates?
muscular: biceps brachial, brachialis, coracobrachialis
cutaneous: lateral surface of forearm
medial cord - sends a branch to what 2 nerves and what muscle?
median, ulnar, and pectorals major
ulnar nerve innervates?
adductor pollicus, small digital muscle, flexor carpi ulnaris, medial surface of hand.
median nerve innervates?
pronator quadrates/teres, distal flexors, flexor carpi radialis, palmaris longus, anterior/later surface of hand
posterior cord gives rise to, which then innervates
axillary nerve: deltoid, teres minor, shoulder skin
radial nerve: triceps brachial, ancones, extensor carpi radialis longus, brachioradialis, supinator, extensor digitorum, abductor pollicus, posterior/lateral arm skin, radial side of hand skin
Lumbar Plexus has what two nerves, and what trunk, which innervate what muscles,
femoral nerve: quadriceps memories, sartorial, pectinous, iliopsoas
obturator nerve: gracilis, obturator externes, adductor Magnus/bravis/longus
lumbosacral trunk: care axons from lumbar plexus to sacral plexus
Sacral Plexus goes into what nerves
superior gluteal, inferior gluteal, sciatic, tibial, common fibular
superior gluteal nerves innervates
gluteus minimus, gluteus medius, tensor fasciae latae
inferior gluteal nerve innervates
gluteus maximus
sciatic nerve innervates
semimembranous, semitendinous, adductor Magnus
tibial nerve innervates
flexion of knee, plantar flexors, flexors of toes, fibulas longs
common fibular nerve innervates and dived into what
short head of biceps femurs, fibulas longus
divides into superficial deep and deep fibular nerves which innervate fibularis braves, tibias anterior and toe extensors.
