If you do uncertain things sniffing things like markers it will kill your brain cells,your organs,cells, and your other stuff is important. Stem cells are sells that can change into other cells. Cells have different jobs then each other for example red blood cells carry oxygen to your body and white blood cells kill infections and kill the flu. Cells form tissues, tissues for organs, organs form systems, and the systems work together to keep us alive!
I think that they had to adapt to the world by being able to breathe and eat.
I think that they had to adapt to the world by being able to breathe and eat.