The cell structures that perform a specific function are called organelles.

Here's why:

* Organelles are like tiny organs within a cell.

* Each organelle has a specialized role in keeping the cell alive and functioning.

* For example, the mitochondria are responsible for producing energy, the nucleus stores genetic information, and the ribosomes create proteins.

So, think of organelles as the mini-machines that make up a cell, each with its own task to keep the whole cell working.