I think they speed up reactions :P
They're similar because they're both methods the cell uses to make ATP. ... Fermentation takes place without oxygen (also known as anaerobic), so less ATP is produced from each molecule of glucose. Another difference is that the byproducts of cellular respiration are always water and carbon dioxide.
I hope this helps
Pic C goes in box A
Pic A goes in box B
Pic B goes in box C
