Because it's partially permeable membrane so it won't let anything get inside the leaf so by this cuticle the leaf is protected not to let any foreign substances in and preventing loss of water
It acts as a reactant in a chemical reaction.
The answer is Start Codon.
The most common organisms with exoskeletons are arthropods which include insects (bees, ants), arachnids (spiders) and crustaceans (lobsters and crabs).
