Answer:ATP is required for muscle contraction. Four sources of this substance are available to muscle fibers: free ATP, phosphocreatine, glycolysis and cellular respiration. A small amount of free ATP is available in the muscle for immediate use
Explanation:
Under the leaf, but a microscope must be used.
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The topic is different from the theme because of the study
<span>the record of descent of an animal, showing it to be purebred.</span>