They use evidences. Hope it helps
Just like the adaptation of humans and animals to the environment, the same also applies for bacteria and viruses.
After so many years of Penicillin being used as the main anti-bacterial cure, bacteria formed resistance due to constant environmental presence.
It provides increased efficiency
Hey Brainly Student!
I found this in wonderopolis.org: “Scientists concluded that the average human body contains approximately 37.2 trillion cells! Of course, your body will have more or fewer cells than that total, depending upon how your size compares to the average human being, but that's a good starting point for estimating the number of cells in your own body!”
This is an estimation and there is not an exact amount because everyone is different :)
