Vocabulary words from the AP Edition of Campbell Biology, Chapter 17.
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| 281356136 | gene expression | process by which DNA directs protein synthesis | 0 | |
| 281356137 | transcription | the synthesis of RNA under the direction of DNA | 1 | |
| 281356138 | messenger RNA | carries a genetic message from the DNA to the protein-synthesizing machinery of the cell | 2 | |
| 281356139 | translation | synthesis of a polypeptide, which occurs under the direction of mRNA | 3 | |
| 281356140 | ribosomes | complex particles that facilitate the orderly linking of amino acids into polypeptide chains | 4 | |
| 281356141 | primary transcript | the initial RNA transcript from any gene, including those coding for RNA that is not translated into a protein | 5 | |
| 281356142 | triplet code | a set of three-nucleotide-long words that specify the amino acids for polypeptide chains | 6 | |
| 281356143 | template strand | the strand which provides the template for ordering the sequence of nucleotides in an RNA transcription | 7 | |
| 281356144 | codons | a three-nucleotide sequence of RNA or DNA which specifies an amino acid or start/stop signal | 8 | |
| 281356145 | promoter | DNA sequence where RNA polymerase attaches and initiates transcription | 9 | |
| 281356146 | terminator | in bacteria, the sequence that signals the end of transcription | 10 | |
| 281356147 | transcription unit | the stretch of DNA that is transcribed into an RNA molecule | 11 | |
| 281356148 | transcription factors | a collection of proteins which mediate the binding of RNA polymerase and the initiation of transcription | 12 | |
| 281356149 | transcription initiation complex | the whole complex of transcription factors and RNA polymerase II bound to the promoter | 13 | |
| 281356150 | TATA box | a promoter DNA nucleotide sequence | 14 | |
| 282213860 | 5' cap | a modified form of a guanine nucleotide added onto the 5' end of an RNA molecule | 15 | |
| 282213861 | poly-A tail | an enzyme adds 50-250 more adenine nucleotides to the 3' end of an RNA molecule | 16 | |
| 282213862 | RNA splicing | stage of RNA processing in which introns are cut out and exons spliced together | 17 | |
| 282213863 | introns | the noncoding segments of nucleic acid that lie between coding regions | 18 | |
| 282213864 | exons | the segments of nucleic acid which are eventually expressed, normally by translation into amino acid sequences | 19 | |
| 282213865 | spliceosome | a large complex made up of proteins and RNA molecules that splices RNA by interacting with the ends of an RNA intron, releasing the intron and joining the two adjacent exons | 20 | |
| 282213866 | alternative RNA splicing | a type of eukaryotic gene 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 | 21 | |
| 282213867 | domain | an independently folding part of a protein | 22 | |
| 282213868 | transfer RNA | the interpreter of a series of codons along a messenger RNA molecule | 23 | |
| 282213869 | anticodon | a nucleotide triplet which base-pairs with a complementary codon on mRNA | 24 | |
| 282213870 | aminoacyl-tRNA synthetases | a family of related enzymes which carry out the correct matching up of tRNA and amino acid | 25 | |
| 282213871 | wobble | flexibility in the base-pairing rules in which the nucleotide at the 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 | 26 | |
| 282213872 | ribosomal RNAs | proteins and RNA molecules which make up ribosomal subunits | 27 | |
| 282213873 | peptidyl-tRNA site | holds the tRNA carrying the growing polypeptide chain | 28 | |
| 282213874 | aminoacyl-tRNA site | holds the tRNA carrying the next amino acid to be added to the chain | 29 | |
| 282213875 | exit site | site from which charged tRNAs leave the ribosome | 30 | |
| 282213876 | polyribosomes | a group of several ribosomes attached to, and translating, the same messenger RNA molecule | 31 | |
| 282213877 | signal peptide | a sequence of about 20 amino acids at or near the leading end of a polypeptide that targets it to the endoplasmic reticulum or other organelles in a eukaryotic cell | 32 | |
| 282213878 | signal-recognition particle | a protein-RNA complex that recognizes a signal peptide as it emerges from a ribosome and helps direct the ribosome to the endoplasmic reticulum by binding to a receptor protein on the ER | 33 | |
| 282213879 | point mutations | chemical changes in a single base pair of a gene | 34 | |
| 282213880 | base-pair substitution | the replacement of one nucleotide and its partner with another pair of nucleotides | 35 | |
| 282213881 | missense mutations | substitutions that change one amino acid to another one | 36 | |
| 282213882 | nonsense mutation | a point mutation changes a codon for an amino acid into a stop codon | 37 | |
| 282213883 | insertions | additions of nucleotide pairs in a gene | 38 | |
| 282213884 | deletions | losses of nucleotide pairs in a gene | 39 | |
| 282213885 | frameshift mutation | alters the reading frame of the genetic message, occurs whenever the number of nucleotides inserted or deleted is not a multiple of three | 40 | |
| 282213886 | mutagens | a number of physical and chemical agents which interact with DNA in ways that cause mutations | 41 |
