So we can easily classify animals and distinguish their relationships
If a person is shot, and the bullet destroys the part of the brain called the medulla, which maintains basic life functions (heart rate, breathing), there is virtually no chance for surviving that injury
The health effects of drinking contaminated water can range from no physical impact to severe illness or even death. Some of the effects of drinking contaminated water can be immediate, or not noticed for many years. These include gastrointestinal and stomach illnesses like: nausea.
The answer is amino acid.