| A | B |
|---|
| transformation | a change in genotype and phenotype due to the assimilation of external DNA by a cell |
| bacteriophages | viruses that infect bacteria; "bacteria eaters" |
| double helix | two starnds helical in shape |
| semiconservative model | one old strand and one new strand |
| origins of replication | where DNA replication begins |
| replication fork | where new strands of DNA are elongating during replication |
| DNA polymerase | elongates DNA |
| leading strand | new strand synthesized in 5' to 3' direction |
| lagging strand | strand that elongates away from replication fork |
| DNA ligase | joins backbone to make new DNA strand; zips up DNA |
| primer | already exhisting RNA chain |
| primase | enzyme that joins RNA nucleotides to make the primer |
| helicase | "unzips" DNA at replication fork |
| single-strand binding protein | line up next to unpaired DNA strands while they serve as templates for new strands |
| mismatch repair | special enzymes used to fix incorrectly paired nucleotides |
| nuclease | DNA-cutting enzyme |
| nucleotide excision repair | when nucleotides are filled in by either DNA polymerase and ligase |
| telomeres | at ends of eukaryotic chromosomal DNA molecules |
| telomerase | enzyme that catalyzes lenghtening of telomeres |
