The organelle that releases stored energy from sugars is called a mitochondrion.

Here's why:

* Mitochondria are often referred to as the "powerhouses" of the cell.

* They are responsible for cellular respiration, a process that breaks down glucose (sugar) in the presence of oxygen to produce ATP (adenosine triphosphate).

* ATP is the primary energy currency of cells, used to fuel various cellular processes.

Let me know if you have any other questions!