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(biochemistry) Any of a class of energy storage compounds, chiefly found in muscular tissue in animals, allowing a high-energy phosphate pool to be maintained in a concentration range, which, if it all were ATP, would create problems due to the ATP consuming reactions in these tissues.

Creatine kinase reaction

(biochemistry) Any of a class of energy storage compounds, chiefly found in muscular tissue in animals, allowing a high-energy phosphate pool to be maintained in a concentration range, which, if it all were ATP, would create problems due to the ATP consuming reactions in these tissues.

Phosphagen System (ATP-PCr) and Purine Nucleotide Cycle (PNC)