<span>the first question, no matter what.</span>
A neurotransmitter
Hope this helps... mark as Brainliest plz
A twitch is defined as a single, brief contraction period and then relaxation period of a skeletal muscle in response to a single stimulation. Contraction period involves receptive power strokes that pull the thin filaments past the thick filaments shortening sacromeres and muscle tension increases as the sacromeres shorten. Relaxation period begins with or release of cross bridges resulting from the return of Ca2+ back to sarcoplasmic reticulum. The strength of skeletal muscle contractions can be broadly separated into twitch, summation, and tetanus. A twitch is a single contraction and relaxation cycle produced by an action potential within the muscle fiber itself.
They form when continents collide; this boundary is a convergent / collision
There is never any shortage of drinking water because we have ton of filtration companies that turn river water to clean fresh drinking water.And again you can always drink tap water.Hope this helps!
