1. Aerobic respiration “with oxygen”
Anaerobic respiration
“without oxygen”
Anaerobic respiration is fermentation
Some organisms can only use fermentation (obligate anaerobes)
Some will undergo aerobic if oxygen is present, but anaerobic if it is not (facultative anaerobes)

2. Some organisms require aerobic respiration, but have specialized CELLS that can undergo anaerobic
EX: Humans and their muscle cells

3. Fermentation
Anaerobic process by which pyruvate is converted into another molecule in order to regenerate NAD+
2 kinds
Alcoholic fermentation
Lactic acid fermentation

4. Alcoholic fermentation

5. Lactic acid fermentation