Now, finally, in terms of the protein metabolism, liver cells can also convert ammonia in the blood into urea, which is then excreted by our kidneys. So when our glucose concentration in the blood runs low, when it is very low, what the liver cells can do is they can actually break down proteins into amino acids and they can use those amino acids to transform the amino acids into ATP molecules. In the process, we produce ammonia, which is a toxic substance. So what the liver does is it takes the ammonia, a toxic substance, and it basically transforms it into urea, which is excreted by the kidneys to outside of our body. So the second important function of the liver is in detoxification. So this basically means taking toxic substances that are detrimental to our body and transforming them into less toxic substances that can be released by our body.