Which organelle is known as the powerhouse of the cell?

The mitochondria are known as the powerhouse of the cell because they are the primary sites of energy production through the process of cellular respiration. This organelle converts the energy stored in food molecules, particularly glucose, into adenosine triphosphate (ATP), which is the energy currency of the cell. The process involves a series of biochemical reactions, including glycolysis, the citric acid cycle, and oxidative phosphorylation. Mitochondria have a unique double membrane structure that facilitates their function, with a folded inner membrane that increases the surface area for reactions to occur.

In contrast, the chloroplast is involved in photosynthesis, allowing plant cells to convert solar energy into chemical energy. The nucleus serves as the control center of the cell, housing genetic material, while the endoplasmic reticulum is primarily involved in the synthesis and transport of proteins and lipids. Each of these organelles plays essential roles in cellular function, but it is the mitochondria that specifically generate the ATP required for various cellular activities, marking them as the powerhouse of the cell.