why mitochondria is known as powerhouse of cell and ATP is energy currency of cell
Mitochondria is known as the power house of the cell as it is the organelle where energy is generated in the form of ATP's. Food is broken down into simpler components and energy is released from them through the process of cellular respiration. Cellular respiration occurs in mitochondria and energy from food is converted into ATP's.
ATP is known as the energy currency of the cell as ATP is used to store and transfer energy in cell. Energy released from food is stored in the form of ATP and ATP are then used to carry out various functions of the cell. Just like we use money to buy various things, cells use ATP to carry out various reactions. Therefore, it is referred to as energy currency of the cell.