In protists respiration occurs in the mitochondria. Oxygen is taken in and goes to the mitochondria and carbon dioxide is produced.
Annelid worms breathe right through their skin. Oxygen diffuses into the body directly into the blood.
Insects breath through spiracles and since they do not have lungs, go into a series of tubes called the tracheal system.
Land amphibians breathe through their skin and ones that live in water use gills. the oxygen goes into their lungs and into the blood system and carbon dioxide is breathed out.
Mammals breathe into their mouths and the oxygen goes to the lungs. the oxygen is then transported to blood cells and carbon dioxide is breathed out.
Non vascular plants take in carbon dioxide through their skin, and into the cells, as a bi product oxygen is made. the oxygen is then diffused out of the plant.