The process in science that uses chemicals to break down food and worn-out cell parts is called lysosome.

Here's why:

* Lysosomes are cell organelles (tiny structures within cells) that act like the "recycling center" or "garbage disposal" of the cell.

* They contain powerful enzymes, which are biological catalysts that speed up chemical reactions. These enzymes break down various materials, including:

* Food particles taken in by the cell through a process called phagocytosis.

* Worn-out or damaged cell parts (organelles) in a process called autophagy.

* Foreign invaders like bacteria and viruses.

So, lysosomes use a cocktail of chemicals (enzymes) to break down these materials, essentially recycling them into useful components or eliminating harmful substances.