| A | B |
| messenger RNA (mRNA) | RNA copy of DNA instructions sent to ribosome |
| transcription | DNA copies instructions into mRNA |
| translation | mRNA, rRNA, and tRNA meet at ribosome to make a protein |
| genetic code | 3 nitrogen bases determine an amino acide in a protein |
| Marshall Nirenberg | experimented with artificial RNA sequences to determine codons |
| codon | 3 nitrogen bases in DNA or mRNA which name a specific amino acid |
| transfer RNA (tRNA) | cross shaped RNA molecule that carries a specific amino acid to the ribosome |
| ribosomal RNA (rRNA) | RNA molecule that is part of ribosome: attachment point for mRNA |
| reverse transcriptase | enzyme used to copy viral RNA of retoviruses |
| retrovirus | virus whose genetic information is carried in RNA molecules |
| RNA polymerase | enzyme that opens DNA and form mRNA from DNA template |
| transcription initiation | RNA polymerase attaches to promoter unwinding DNA |
| transcription elongation | RNA polymerase moves along DNA forming RNA transcript |
| transcription termination | RNA polymerase and RNA transcript released from DNA terminator region |
| splicing | post transcription enditing of RNA transcript to form mRNA |
| introns | pieces of RNA transcript cut out when mRNA is spliced |
| exons | pieces of RNA transcript joined together to make mRNA |
| anticodon | 3 nitrogen bases in tRNA that match mRNA codons |
| tRNA charging | attaching proper amino acid tRNA with proper matching anticodon |
| P site of ribosome | active site on ribosome that holds tRNA bearing the growing polypeptide chain |
| A site of ribosome | active site on ribosome that holds tRNA bearing next amino acid added to chain |
| reading frame | concept that starting at proper point maintains codon translation |
| signal sequence | binds to ER receptor that carries polypeptide into organelle for transport to cell |
| translation initiation | mG cap of mRNA, methionine tRNA into p site, ribosome cloeses |
| translation elongation | a site accepts anticodon of tRNA, amino acids bond to chain, slide over to p site |
| translation termination | ending codon in a-site attracts protein to release ribosome and polypeptide |