Nerve and Muscle - Definition


O depth     : diff btween oxygen needed and oxygen available
starling law : force of contraction of muscle is DP to its initial lenght..
rigor mortis : stiffness of the muscle which occur after death without actio potential.
SMT          : contrction followd by relaxation resulting from single max stimulus to the muscle.
exitation contraction coupling : link between mechanical and electrical change in the muscle
myasthenia gravis : easy fatigueability of muscle, heridatoty disease.
excitability : ability of any living tissue to respond to a stimulus.
stimulus : any change in the internal or external environment surrounding a living tissue that cause it to respond.

Rheobase (R) : minimal intensity of a stimulus that can stimulate
utilization time (T) : time needed by threshold stimulus to stimulate.
Chronaxie (C) : time neede by a current of a double the rheobase intensity to stimulate
minimal time (t) : minimal duration required for stimulation

subthreshold : local excitatory state
threshold @ more : action potential & nerve impulse

nerve impulse : physico-chemical disturbance produced by a stimulus of threshold intensity or more

RESTING MEMBRANE POTENTIAL RMP : potential diff between outer and the inside of the nerve fibr
ACTION POTENTIAL : series of electric change that accompany the nerve impulse.

Skeletal muscle : muscle attached to skeleton
Cardiac muscle : fiber that are present only in the heart
Smooth muscle : fiber are present in hollow viscera and blood vessel.

1- Skeletal muscle
Sarcolemma : muscle fiber membrane
Sarcoplasm : cytoplasm of the muscle fiber
Sarcomere : contractile unit of the skeletal  muscle fiber. Extend from Z-Z line
Cross bridge : small projection from surface of the myosin filament, they interact with actin causing contraction


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