(1) The varying number of muscle fibers that contract
<span>In most muscles, the number of muscle fibers in different motor units ranges from a few to hundreds. The nervous system can thus regulate the strength of contraction in a muscle by determining how many motor units are activated at a given instant and by selecting large or small motor unties to activate. </span>
some muscles are almost always partially contracted. In such muscles, the nervous system my alternate activation among the motor units, reducing the length of time any one set of fibers is contracted. Prolonged contraction can result in muscle fatigue due to the depletion of ATP and dissipation of ion gradients required for normal electrical signals.ing.
<span>(2) varying the rate at which muscle fibers are stimulated </span>
<span>single action potential produces a twitch lasting about 100 msec or less. If a second action potential arrives before the muscle fiber has completely relaxed, the two twitches add together, resulting in greater tension. Further summation occurs as the rate of stimulation increases. When the rate is so high that the muscle fiber cannot relax at all between stimuli, the twitches fuse into one smooth, sustained contraction called tetanus.</span>
Answer:
The answer is between 15 and 25 percent.
Explanation:
According to The United States Department Of Agriculture (USDA) and National Agricultural Library (NAL), the current Acceptable Macronutrient Distribution Range (AMDR) for saturated fat is between 15 percent and 25 percent of their daily caloric intake for adults.
I hope this answer helps.
I don’t know the first two but the last one the thousands of subunits are called nucleotides
<span>After
digestion, an amino acid not absorbed by the body and not used to build
proteins will first be subjected to removal from its amino group. If they are
not used for protein synthesis, amino acids becomes part of the metabolism
process. The body has the capability to create a subset of amino acids, also
known as non-essential amino acids because we don’t have requirement for them
in our diet. </span>
Microtubules provide a rigid structure, or cytoskeleton
