Question

Myocardium must rhythmically contract for a lifetime. This requires a considerable amount of energy production by the cells. You would expect to see a relatively high amount of which organelle in these cells

Answer 1

The answer would be mitochondria

The primary form of energy that the cell use are come from ATP. The body could produce ATP through different path of metabolism, but the highest amount of ATP produced from electron transport chain. Mitochondria is the main organelle of the cell that produce ATP because it allow the cells to do electron transport chain.