Matter cannot be created or destroyed in chemical reactions. This is the law of conservation of mass. In every chemical reaction, the same mass of matter must end up in the products as started in the reactants. Balanced chemical equations show that mass is conserved in chemical reactions.
The correct answer is a Bar Graph.
Cellular differentiation describes how different cells perform different processes and have unique functions. There are at least 250 cells in the human body and each one plays a different role, and <em>all</em> of them are crucial to the body's ability to maintain homeostasis. For example, liver cells produce proteins that are important in blood clotting. If these cells are damaged, blood will not clot properly. If blood does not clot, a body cannot maintain homeostasis and the person will fall ill.
TL;DR: every cell plays its part and keeps the organism alive.
Yes they do without it they could not produce protein.