Here's why:

* Mitochondria are often called the "powerhouses" of the cell. They are responsible for the process of cellular respiration, where glucose is broken down to produce ATP (adenosine triphosphate), the primary energy currency of the cell.

* Other organelles may play roles in energy production, but not in the same way as mitochondria:

* Chloroplasts, found in plants, are responsible for photosynthesis, which converts light energy into chemical energy.

* Ribosomes are involved in protein synthesis, which is essential for many cellular functions, including energy metabolism.

Let me know if you have any other questions!