Explanation:
Mitochondria are the power house of the cell, they priduce atp from a series of processes. The ATP or Adenosine triphosphate is broken down to ADP or Adenosine diphosphate. To put simply emergy is released when a bond is broken due to hydrolysis which releases energy. More mitochondria are found in areas where mkre energy is required such as cells in,muscles, liver cells,and brain cells. ATP is extremely important for the heqrt as wnergy is required for the pumping of blood by contraction of the heart muscle.
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can give a detailed exp if required