Question

Why is it significant that all biological systems use L-amino acids and D-sugars?

Answer 1

Answer- All biological systems must use L-amino acids and D-sugars because they are essential for life. The structures of L-amino acids and D-sugars allow molecules to perform functions which are necessary for the living systems. Amino acids and sugars have other isomers too, but they do not perform these functions correctly. The main reason why L-amino acids and D-sugars are significant is that all the energy in the form of these two isomers that organisms obtain can also be used by other organisms as sources of fuel for their respective body processes. This is because these isomers have the same function and the same properties in all organisms.