Which term best describes the establishment of a new
community of organisms after a volcano?

Pioneer species is the general name for the first organisms to move into a disturbed environment or to grow after a volcanic eruption covers an area with lava.

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nucleic acid molecules are incredibly complex, containing the code that guarantees the four different nucleotide units comprise dna, the nucleic acid of interest to the genealogist. and one of four nitrogen-containing molecules called nucleotides

the answer is b.) hydrogen bonds between bases.