Which organelle is known as the powerhouse of the cell?

The mitochondria are known as the powerhouse of the cell because they are the organelles responsible for producing energy in the form of adenosine triphosphate (ATP) through the process of cellular respiration. This process involves breaking down glucose and other molecules, allowing cells to access the energy required for various functions, such as growth, repair, and maintenance. The ATP produced in the mitochondria fuels many cellular processes, making them essential for the survival and proper functioning of eukaryotic cells.

In contrast, ribosomes are responsible for protein synthesis, and the nucleus contains the cell's genetic material and oversees activities such as cell division and gene expression. Glucose is a simple sugar that serves as a primary energy source for cells, but it is not an organelle. Understanding the role of mitochondria helps clarify why they hold such an important title within the cell.