What enables dna to have so many variations with only 4 chemicals?

The earth consists of a variety of different organisms. despite their diversity, however, some similarities on the structural and metabolic levels may be seen. these similarities can be attributed to a. similarities among organisms in their proteins and nucleic acids. b. the ability of organisms to readily adapt to sudden environmental changes. c. similarities in organisms' habitats and niches. d. the ability of all organisms to interbreed and produce new species.

Phosgene is a chemical agent that is formed by decomposition of chlorinated hydrocarbon solvents by ultraviolet radiation. a. false b. true

Forensic scientists think they know the identity of a skeleton. what rule should they use to select a relative whose dna could be used to try to confirm the identity?