Which cell organelle is known as the powerhouse of the cell?

The mitochondria are often referred to as the "powerhouse of the cell" due to their essential role in producing adenosine triphosphate (ATP), the energy currency of the cell. Mitochondria are responsible for the process of cellular respiration, where they convert nutrients from food into ATP through a series of biochemical reactions, including the Krebs cycle and oxidative phosphorylation. This process is crucial for providing the energy required for various cellular functions and processes, such as muscle contraction, nerve impulse propagation, and biosynthesis. The structure of mitochondria, with their double membrane and inner folds known as cristae, facilitates these energy-producing reactions. This unique function distinguishes mitochondria from other organelles, such as ribosomes, the nucleus, or the endoplasmic reticulum, which have different roles within the cell.