Aerobic respiration needs oxygen in order to produce energy (ATP). Aerobic is much more efficient than anaerobic metabolism.

Aerobic Cellular Respiration
Aerobic Cellular Respiration, By Maya Pillai, Buzzle.com, A combination of text and illustrations.
Aerobic Respiration
Aerobic Respiration, Brightstorm Videos, Patrick Roisen, Video length: 03:44
Exercise and Aerobic Respiration
Exercise and Aerobic Respiration How Stuff Works Brief, but excellent article.
What Is Aerobic Respiration?
What Is Aerobic Respiration?, Written by Ken Black, WiseGeek.com, All-text article on how aerobic respiration works, glycolysis, the Krebs cycle, and more.
Why Do We Breathe? Aerobic Cellular Respiration
Why Do We Breathe? Aerobic Cellular Respiration, By Tami Port, Science Prof Online, "Aerobic cellular respiration is the series of reactions that, with the help of oxygen, make ATP (cellular ene