| A | B |
|---|
| adenine | a purine base; a component of nucleotides |
| bacteriophage | virus that infects bacteria |
| base-pairing rules | Chargaff's rules that state the amount of adenine equals the amount of thymine and the amount of quanine equals the amount of cytosine |
| complementary | characteristic of nucleic acids in which the sequence of bases on one strand determines the sequence of bases on the other |
| cytosine | nitrogenous base of the pyrmidine class; component of RNA and DNA |
| dexyribose | five-carbon sugar that is a component of DNA nucleotides |
| DNA polymerase | enzyme that catalyzes the replication of DNA |
| double helix | spiral-staircase structure characteristic of the DNA molecule |
| exon | sequence of nucleotides that gets translated and transcribed |
| helicase | enzyme that unwinds a DNA molecule's double helix before replication |
| intron | segment of mRNA transcribed from eukaryotic DNA but removed before translation of mRNA into a protein |
| guanine | nitrogen base of the purine class; component of DNA and RNA nucleotides |
| multigene family | group of genes that has evolved from a single ancestral gene and is characterized by existance of multile copies |
| nucleotide | subunit of nucleic acids consisting of a nitrogenous base, a sugar, and a phosphate group |
| purine | class of organic, nitrogenous molecules in nucleic acids that have a single ring of carbon and nitrogen |
| pyrimidine | class of organic, nitrogenous molecules in nucleic acids that have a single ring of carbon and nitrogen |
| replication | process of synthesizing a new strand of DNA |
| replication fork | point at which the couble heliz of DNA separates so that it can be copied |
| thymine | nitrogenous base of the pyrimidine class; component of DNA |
| transformation | the transfer of genetic material from one organism to another; first observed by Griffith |
| vaccine | substance prepared from killed or weakened pathogens and introduced into a body to produce immunity |
| virulent | referring to the deadliness of a disease-causing agent |
