Muscle Physiology

Front 1

what type of muscle likely possesses the most mitochondria?

Back 1

cardiac

Front 2

list those types of muscle that have the most ATPase in decreasing order

Back 2

Skeletal > Cardiac> Smooth

Front 3

which type of cells possess pacemakers?

Back 3

smooth (slow)
cardiac (fast)

Front 4

what muscle type has the greatest length of sarcomeres?

Back 4

skeletal (3.65 microm)
cardiac (2.6 microm)

Front 5

Which muscle types exhibit graded contractions?

Back 5

smooth
skeletal

Front 6

where is the operating tension of skeletal muscle?

Back 6

on peak of tension curve

Front 7

where is the operating tension of cardiac muscle?

Back 7

on the rising portion of the tension curve

Front 8

what is the typical type receptors found at the post synaptic aspect of the skeletal motor neuron?

Back 8

ligand gate Nicotinic channels

Front 9

what is the NT for skeletal muscle?

Back 9

Ach

Front 10

what is a primary SNARE protein involved in vesicle binding and release within presynaptic bouton

Back 10

Synaptobrevin

Front 11

what toxin causes the blockage Na+ channels both on Post and Pre-synaptic terminals of muscle cells?

Back 11

Tetrodotoxin

Front 12

Botulin toxin has what effect on the NMJ?

Back 12

blocks Ach release from motor neuron
by dissolving SNARE proteins

Front 13

Physostigmine and Neostigmine have what action on the NMJ?

Back 13

cholinesterase inhibitors

Front 14

Orgonophosphate

Back 14

irreversible cholinesterase inhibitors

Front 15

alpha-bungarotoxin or Curare act on the NMJ as _______ causing _______?

Back 15

competetive inhibitors
muscle paralysis

Front 16

what is the action of Dendrotosin on NMJ

Back 16

blocks K+ channels

Front 17

ionotropic receptor is involved in what type of NMJ synapse?

Back 17

somatic NMJ (skeletal)

Front 18

metabotropic receptors are involved in what type of NMJ synapse

Back 18

cardiac
parasympthetic mucarinic

Front 19

what channels are found in T tubules that fxn to release extracellular Ca++ into terminal cistern to promote mucsle contraction?

Back 19

DHP channels

Front 20

what channels are responsive to Ca++ in the SR of muscle cells causing release of more stored Ca++ to cause muscle contraction

Back 20

Ryanodine channels

Front 21

What is the function of the 'I' site of Troponin?

Back 21

attaches to actin - determines inactivity of muscle filaments

Front 22

What is the fxn of the 'C' site of Troponin?

Back 22

calcium binding site

Front 23

What is the fxn of the 'T' site of Troponin?

Back 23

attaches troponin to bine Tropomyosin site

Front 24

what is the fxn of the alkali head sub-unit of myosin?

Back 24

stabilizes myosin

Front 25

what is the fxn of the regulating head subunit?

Back 25

regulates ATPase

Front 26

what is necessary to 're-cock' and renew the cross-bridge cycle and if not what occurs?

Back 26

ATP
Rigor Mortis

Front 27

The degree of NTs is based upon the the current produced by what _____ and ultimately a product of ______ channels

Back 27

- Na+ from axonal process
- Ca++ channels

Front 28

Where are SNARE proteins located?

Back 28

presynaptic neurotransmitter vesicle membranes

Front 29

Synapsin are a _____ protein

Back 29

SNARE

Front 30

'fusion promoting factor' that functions to promote movement of NTs to active sites on presynaptic membrane =

Back 30

Synapsins

Front 31

a protein receptor for Ca++ on the vesicle membrane that senses Ca++ rise and leads to exocytosis of NT

Back 31

Synaptogamin

Front 32

promotes fusion of vesicles to pre-synaptic membrane and is essential for NT release into cleft

Back 32

Synaptobrevin

Front 33

what can potentially dissolve SNARE proteins on NT vesicles?

Back 33

neurotoxins of:
- Clostridium tentani (tetanospasmin)
- Clostridium botulinum

Front 34

dirt borne toxin affecting interneuronal firing?

Back 34

tetanus toxin

Front 35

what cell does the Tetanus toxin target?
and what is the mechanism?

Back 35

limiting glycine release by destroying veiscle membranes that allow for exocytosis --> prolonged contraction

Front 36

usually food bourne neuro toxin?

Back 36

botunlinum toxin

Front 37

the tissues targeted by botulinum toxin are specifically?

Back 37

ANS --> smooth muscle

Front 38

do precision movements require small or large motor units?

Back 38

small: smaller NMJ:fiber ratio

Front 39

this nerve innervates the flexors of the arm and forearm (biceps brachii, coracobrachialis, brachialis)

Back 39

musculotaneous n.

Front 40

this nerve will flex the muscles of the arm, forearm, wrist, hand and THUMB

Back 40

median n.

Front 41

this nerve innervates the muscles which extend the arm, forearm, wrist and hand

Back 41

radial n.

Front 42

this nerve innervates the muscles of the flexors of the wrist and digits, and the deep abductor and adductors of the digits

Back 42

ulnar n.