Physiology: Neuro

Front 1

skeletal muscle excitation

Back 1

neuromuscular transmission
single cell for a single neuron, but a neuron can innervate several muscle cells
somatic

Front 2

smooth muscle excitation

Back 2

synaptic transmission, hormones, electrical signaling, pacemaker potential
one neuron connects to a cell multiple times
autonomic

Front 3

Cardiac muscle excitation

Back 3

pacemaker potential across gap jxns
autonomic nerves modulate but dont initiate signal

Front 4

Multi-unit smooth muscle

Back 4

each cell innervated seperately, contracts seperately
for fine motor control, no gap jxns
ciliary of eye, piloerector skin muscles

Front 5

Unitary smooth muscle (visceral)

Back 5

sheets of SM bound by gap jxns for electrical comm. b/t
found in organs

Front 6

SM action potential: Spike

Back 6

inward Ca2+ depolarizes cell, opening more voltage gated Ca2+ channels
action potential is lower than skeletal/cardiac due to channels opening slower than Na+

Front 7

SM action potential: Plateau

Back 7

repolarization delayed for 1000msec, causing plateau
causes prolonged contraction (uterus)

Front 8

SM action potential: slow waves

Back 8

regular, repetitive membrane potential in spontaneous electrical activity
if strong, can initiate action potential

Front 9

Muscle contraction: Attached State

Back 9

ADP releases, myosin head of heavy chain bound to light chain

Front 10

Muscle contraction: Released State

Back 10

ATP binds to myosin head, causing it to release from light chain

Front 11

Muscle contraction: Cocked State

Back 11

ATP becomes ADP, causing myosin head to pivot and cock back

Front 12

Muscle contraction: Cross-Bridge State

Back 12

myosin head binds to a new spot on actin light chain

Front 13

Muscle Contraction: Power-Stroke

Back 13

inorganic phosphate detaches from myosin head, causing conformational change and the myosin head bending back to original position

Front 14

Excitation-contraction: Skeletal

Back 14

depolarization opens Ca2+ channels from Sarcoplasmic Reticulum, allowing Ca2+ to attach to Troponin C and starting muscle contraction

Front 15

Excitation-contraction: Cardiac

Back 15

depolarization opens Ca2+ channels from Sarcoplasmic Reticulum, allowing Ca2+ to attach to Troponin C and starting muscle contraction

Front 16

Excitation-contraction: Smooth

Back 16

1. Ca2+ thru voltage gated channels
2. Ca2+ from SR, either Ca2+ induced or IP3
3. Ca2+ thru voltage INDEPENDENT channels

Front 17

Termination of Muscle Contraction/removal of Ca2+

Back 17

1. Na+/Ca2+ pumps remove from cell
2. Ca2+ is pumped INTO SR
3. Ca2+ is bound to Calreticulin in the SR to aid in sequestering Ca2+ (allows for more to enter SR)

Front 18

Regulation of Contraction: Skeletal

Back 18

summation of contractile forces can increase force

Front 19

Regulation of Contraction: Cardiac

Back 19

Regulating Ca2+ (increased Ca2+ increases contraction)

Front 20

Regulation of Contraction: Smooth

Back 20

balance b/t phosphorylation and dephosphorylation
regulate Ca2+

Front 21

Type 1 muscle, slow twitch

Back 21

Fatigue resistant
oxidative metabolism
high mitochondria
low glycogen

Front 22

Type 2a muscle, fast twitch

Back 22

fatigue resistant
oxidative metabolism
higher mitochondria
medium glycogen

Front 23

Type 2b muscle, fast twitch

Back 23

not fatigue resistant
glycolytic metabolism
low mitochondria
high glycogen

Front 24

Free nerve endings characteristics

Back 24

A delta, C
pain, temp, crude touch
slow adaptation

Front 25

Meissner's corpuscles characteristics

Back 25

A beta
touch, pressure
rapid adaptation

Front 26

Pacinian Corpuscle characteristics

Back 26

A beta
Deep pressure, vibration
rapid adaptation

Front 27

Merkel's disk characteristics

Back 27

A beta
touch, pressure
slow adaptation

Front 28

Ruffini's corpuscles characteristics

Back 28

A beta
stretch of skin
slow adaptation

Front 29

Muscle spindle characteristics

Back 29

A alpha and beta
muscle length
slow and rapid adaptation

Front 30

golgi tendon characteristics

Back 30

A beta
Muscle tension
slow adaptation

Front 31

joint receptors characteristics

Back 31

joint position
rapid adaptation

Front 32

rapid adaptation

Back 32

respond quickly and maximally but for a short period

Front 33

slow adaptation

Back 33

receptors fire as long as stimulus is present

Front 34

receptive field

Back 34

minimal amount of skin to perceive 2 simultaneous stimulus
smallest receptive field=most sensitive areas

Front 35

what mechanoreceptors are used in proprioception?

Back 35

Muscle Spindle: muscle length/stretch
Golgi tendon: muscle tension
Joint receptors: position of joint

Front 36

General Nociception

Back 36

carried by A delta (myelinated) and C (unmyelinated) axons
A delta carry dangerously intense stimuli (fast)
C carry polymodal stimuli that are specific to C fibers

Front 37

Sharp First Pain

Back 37

intense enough to activate A delta fibers
small receptive field

Front 38

Second Pain

Back 38

as stimulus increases, C fibers begint to conduct
duller, longer lasting sensation
large receptive field

Front 39

Hyperaglesia

Back 39

enhanced sensitivity to stimulation of area around damaged tissue
due to released substances that enhance neuronal sensitivity

Front 40

Mechanism of referred pain

Back 40

cross talk b/t visceral and somatic system, visceral pain felt cutaneously

Front 41

Phantom pain

Back 41

amputation of a limb
neurons are responding to a tactile stimulation of close proximity

Front 42

central pain regulation

Back 42

pain can be controlled by stimulation in the central midbrain
acupuncture, hypnosis, electrical stimulation

Front 43

pain modulation

Back 43

NT in the ascending pathways can have inhibitory affects on dorsal horn neurons
stimulation of mechanoreceptors can reduce sensation of pain (gate theory, rubbing stubbed toe)