During DNA replication, the two strands separate as the hydrogen bonds connecting the parent strands are broken by an enzyme called helicase. In the DNA molecule (double strand) complementary bases are joined by hydrogen bonds; that is; Adenine paired to thyamine and guanine to cytosine; during replication the enzyme helicase separates the double helix by breaking the hydrogen bonds between the complementary bases.
Answer:
From 1945–1955 the development of penicillin, which is produced by a fungus, along with streptomycin, chloramphenicol, and tetracycline, which are produced by soil bacteria, ushered in the antibiotic age.
Explanation:
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C. no virus contains DNA or RNA
<span>When grains move closer together, eliminating spaces between them, _____ has occurred? </span>compacation