Where does cellular respiration take place?

As in the case of bacteria and protozoans, a single cell can be an entire organism in and of itself. 

In multicellular creatures like higher plants and animals, specialized cell groups are arranged into tissues and organs. Prokaryotic cells and eukaryotic cells are two different types of cells.

Cellular respiration is a stepwise catabolic process in which a respiratory substance is broken down to produce energy as ATP. 

The word itself shows that it is a process that occurs inside the cells of the body.