Why is diffusion insufficient to meet the oxygen requirements of multicellular organisms like humans?

dna damages cause changes in the structure of the genetic material and prevents the replication mechanism from functioning and performing properly. dna damage and mutation have different biological consequences. while most dna damages can undergo dna repair, such repair is not 100% efficient.

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.