The digestive system is necessary for the body's health because it breaks down the food we eat into small pieces that can be absorbed by the body. Without the digestive system, we would not receive all of the nutrients from food.
Bacteria have been the very first organisms to live on Earth
Answer:
I think it's flip if not turn
Molecular clocks use rates of mutation to measure evolutionary time.Mutations add up at a fairly constant rate in the DNA of species that evolved from a common ancestor. The more mutations that happened in each lineage, the greater is the differences between these lineages.
