Question

Does the energy associated with the mechanical work performed by a contracting muscle fiber (cell)derive from the stored potential energy of ionic gradients, or from some other source? Please explain.

Answer 1

Answer:

• The contraction of muscle fiber is triggered by a neuronal impulse. Mitochondria are involved in processes that supplies energy required for the work performed during the contraction of the muscle fibe (cell) and is derived from Adenosine Triphosphate (ATP).
• Hydrolysis of ATP releases ADP, inorganic phosphate and energy. Reactions of aerobic cellular respiration occurs in Mitochondria and requires presence of oxygen to break down food ( stored reserves of glycogen, blood glucose, atty acids etc) thereby generating ATP that is used for contraction of muscles.
• Creatine phosphate (CP) and muscle glycogen are also used to generate muscle ATP, when the levels of ATP in muscles fiber (cells) depletes.