Beause we cut down a lot of trees. Often, so many, that the health of a forest is irreparably damaged. A forest is not just a bunch of trees. It is a whole ecosystem, in which the trees anchor the growth of many other plant and animal species, hold the ground together to prevent erosion, and produce a lot of oxygen to support animal life. If you harvest too many of the trees, the local ecosystem stops being a forest and starts turning into something else
They break down sugar molecules to provide energy for the cell.
Good luck! :)
The part of the amino acid that gives the molecule its unique or characteristic chemical properties would be the R-group. Every amino acid has three main groups in it namely the amino group, carboxyl group and the R group. "R" represents different organic chain that is specific to a certain amino acid which gives different properties of the molecule.