A basic tenet of modern biology, first stated by Matthias Schleiden and Theodor Schwann in 1838–39, that cells<span> are the basic units of structure and function in living organisms. ... A </span>theory<span> of heredity must be reconciled with the </span>cell theory<span>.</span>
Alot of humans might not now they are even harming the systems by smoking or littering.
Answer:
Weathering look at the text book mate
