Why does anaerobic respiration need no oxygen?

Not enough oxygen may reach the muscles during exercise. When this happens, they use anaerobic respiration to obtain energy. Anaerobic respiration involves the incomplete breakdown of glucose. It releases around 5% of the energy released by aerobic respiration, per molecule of glucose. read more

Anaerobic respiration takes place in the cytoplasm, the fluid part. This type of respiration leaves behind large amounts of energy in the lactate molecules or the ethanol. This energy is unusable and must be gotten rid of as waste. One example of the importance of anaerobic respiration is exercise. read more