Cellular respiration is a set of metabolic reactions and processes that take place in the cells of organisms to convert biochemical energy from nutrients into ATP (adenosine triphosphate), and then release waste products. <span>There are </span>3 major<span> steps in </span>cell respiration:<span> glycolysis, Krebs Cycle, and the electron transport chain.</span>
Fossils give information about the time period in which organisms lived in the past.
