Since our bodies are made up of 70 percent water, we need water to keep us from dehydrating, food is important because it has the nutrients and proteins that our bodies need to repair, grow, and keep healthy, and oxygen is also important because it gets carried throughout our blood stream and oxygenates our muscles, without any of these, we would die within a few weeks
If the mutation is beneficial, the mutated organism survives to reproduce, and the mutation gets passed on to its offspring. In this way, natural selection guides the evolutionary process to incorporate only the good mutations into the species, and expunge the bad mutations.
