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The genetic code is the set of rules by which information encoded in genetic material (DNA or RNA sequences) is translated into proteins (amino acid sequences) by living cells. Those genes that code for proteins are composed of tri-nucleotide units called codons, each coding for a single amino acid.
Natural Changes That Can Affect an Ecosystem. Wind, rain, predation and earthquakes are all examples of natural processes which impact an ecosystem. Humans also affect ecosystems by reducing habitat, over-hunting, broadcasting pesticides or fertilizers, and other influences.