Because they do not have an immune system, don't have noses, don't have mouths, and just plain do not have the same functions as animals, insects, or humans. They don't have a heart or a brain, which means they can't catch a cold. They can get diseases however.
The eruption of Mount Saint Helens has proved to have dramatically change the abiotic and biotic factors of its environment. As what was shown in the image just 24 years from its eruption, we can already observe that animal life began to populate the region due to its sufficient vegetation.
"A" bonds with "T", and "G" bonds with "C" (A-T) (G-C)
By ball bearing, lubrication, polishing, adding grease etc
