| A | B |
| virulent | causing a disease |
| nucleotide | the basic building block of a nucleic acid |
| transformation | the changing of characteristics |
| deoxyribose | sugar found in DNA |
| DNA | short for Deoxyribonucleic Acid |
| purine | larger nucleotide bases (adenine and guanine) |
| pyrimidine | smaller nucleotide bases (cytosine and thymine) |
| double helix | description of the molecular shape of DNA |
| replication | the copying of DNA |
| mutagen | substance that causes a gene to mutate |
| RNA | short for Ribonucleic Acid |
| gene expression | the making of a protein from the information in a gene |
| transcription | the part of gene expression in which DNA makes mRNA |
| mRNA | messenger RNA |
| tRNA | transfer RNA |
| translation | the making of a protein from mRNA at a ribosome |
| uracil | replaces thymine in RNA |
| genetic code | the matching of codons with the corresponding amino acids |
| codon | three nucleotides on a strand of mRNA |
| anticodon | three nucleotides on tRNA |
| amino acid | basic building block of protein |