Gamma rays because microwaves, visible light and radio waves wouldn’t come in handy if an astronomer would want to study the composition of planets and stars.
One is that it allows for variation which allows better chance of survival and evolution.
Enzymes are proteins that behave as biological catalysts. They need to have a very specific three-dimensional shape in order for the reaction to occur. If the three-dimensional shape is not formed correctly then the chemical reaction, that is supposed to be promoted by the enzyme, may not occur.
