campbell
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| 346748333 | Beadle and Tatum | Showed that each gene encodes a particular substance ("one gene, one enzyme" concept). | |
| 346748334 | one gene one polypeptide hypothesis | the hypothesis that every gene directs the synthesis of a particular polypeptide chain; originally called the one geneone enzyme hypothesis. | |
| 346748335 | transcription | the organic process whereby the DNA sequence in a gene is copied into mRNA | |
| 346748336 | mRNA | messenger RNA; type of RNA that carries instructions from DNA in the nucleus to the ribosome | |
| 346748337 | translation | the process whereby genetic information coded in messenger RNA directs the formation of a specific protein at a ribosome in the cytoplasm | |
| 346748338 | RNA processing | ..., Modification of RNA before it leaves the nucleus, a process unique to eukaryotes. | |
| 346748339 | primary transcript | An initial RNA transcript; also called pre-mRNA. | |
| 346748340 | triplet code | the normal version of the genetic code in which a sequence of three nucleotides codes for the synthesis of a specific amino acid | |
| 346748341 | template strand | The DNA strand that provides the template for ordering the sequence of nucleotides in an RNA transcript. | |
| 346748342 | codons | A three-nucleotide sequence of DNA or mRNA that specifies a particular amino acid or termination signal; the basic unit of the genetic code. | |
| 346748343 | Nirenberg | determined the first match: UUU coded for the amino acid phenylalanine. | |
| 346748344 | reading frame | the way a cell's mRNA-translating machinery groups the mRNA nucleotides into codons | |
| 346748345 | RNA polymerase | enzyme similar to DNA polymerase that binds to DNA and separates the DNA strands during transcription | |
| 346748346 | terminator | A special sequence of nucleotides in DNA that marks the end of a gene. It signals RNA polymerase to release the newly made RNA molecule, which then departs from the gene | |
| 346748347 | promoter | region of DNA that indicates to an enzyme where to bind to make RNA | |
| 346748348 | TATA box | A promoter DNA sequence crucial in forming the transcription initiation complex. | |
| 346748349 | transcription factors | proteins that switch on genes by binding to DNA and helping the RNA polymerase to bind | |
| 346748350 | transcription initiation complex | The completed assembly of transcription factors and RNA polymerase bound to the promoter. | |
| 346748351 | poly(A) tail | The modified end of the 3' end of an mRNA molecule consisting of the addition of some 50 to 250 adenine nucleotides. | |
| 346748352 | 5' cap | when pre-mRNA is modified the 5 primed end is synthesized first; it is a modified form of a guanine nucleotide | |
| 346748353 | introns | a non-coding, intervening sequence within a eukaryotic gene AKA junk DNA | |
| 346748354 | exons | expressed sequence of DNA; codes for a protein | |
| 346748355 | RNA splicing | process by which the introns are removed from RNA transcripts and the remaining exons are joined together | |
| 346748356 | spliceosome | A complex assembly that interacts with the ends of an RNA intron in splicing RNA, releasing the intron and joining the two adjacent exons. | |
| 346748357 | ribozynes | a RNA molecule that acts as an enzyme | |
| 346748358 | alternative RNA splicing | ..., A type of regulation at the RNA-processing level in which different mRNA molecules are produced from the same primary transcript depending on which RNA segments are treated as exons and which as introns. | |
| 346748359 | domains | a taxonomic category above the kingdom level; the three domains of life are Archaea, Bacteria, and Eukarya | |
| 346748360 | tRNA | short-chain RNA molecules present in the cell (in at least 20 varieties, each variety capable of combining with a specific amino acid) that attach the correct amino acid to the protein chain that is being synthesized at the ribosome of the cell (according | |
| 346748361 | anticodon | group of three bases on a tRNA molecule that are complementary to an mRNA codon | |
| 346748362 | wobble | A violation of the base-pairing rules in that the third nucleotide (5' end) of a tRNA anticodon can form hydrogen bonds with more than one kind of base in the third position (3' end) of a codon. | |
| 346748363 | rRNA | ribosomal RNA; type of RNA that makes up part of the ribosome | |
| 346748365 | P site | one of a ribosome's three binding sites for tRNA during translation. It holds the tRNA carrying the growing polypeptide chain. | |
| 346748368 | A site | holds the tRNA carrying the next amino acid to be added to the chain | |
| 346748370 | initiation | DNA replication is initiated when helicase enzyme breaks the hydrogen bonds holding the base pairs together and the DNA uncoils. The initiation codon is methionine or AUG | |
| 346748372 | elongation | addition of amino acids to the polypeptide chain; continues until it reaches a stop codon | |
| 346748374 | termination | end of mRNA synthesis (i.e., transcription) at the terminator site | |
| 346748376 | polyribosomes | An aggregation of several ribosomes attached to one messenger RNA molecule. | |
| 346748378 | signal peptide | A stretch of amino acids on a polypeptide that targets the protein to a specific destination in a eukaryotic cell. | |
| 346748381 | signal recognition particle | A protein-RNA complex that recognizes a signal peptide as it emerges from the ribosome. | |
| 346748382 | base pair substitution | A point mutation; the replacement of one nucleotide and its partner in the complementary DNA strand by another pair of nucleotides. | |
| 346748383 | missense mutation | The most common type of mutation, a base-pair substitution in which the new codon makes sense in that it still codes for an amino acid. | |
| 346748384 | nonsense mutation | A mutation that changes an amino acid codon to one of the three stop codons, resulting in a shorter and usually nonfunctional protein. | |
| 346748385 | insertions | A mutation involving the addition of one or more nucleotide pairs to a gene, i.e ATG -> ATTG | |
| 346748386 | deletions | one or more bases are removed from gene | |
| 346748387 | frameshift mutations | mutation that shifts the "reading" frame of the genetic message by inserting or deleting a nucleotide | |
| 346748388 | mutagens | Factors in the environment that cause mutations. |
