From Gene to Protein
11742706053 | Gene Expression | process by which DNA directs synthesis of proteins | 0 | |
11742706054 | Transcription | -synthesis of RNA under direction of DNA -DNA serves as template for assembling complementary RNA molecule -resulting RNA molecule faithful transcript of gene's protein-building instructions -occurs in nucleus | 1 | |
11742706055 | Messenger RNA (mRNA) | RNA molecule that carries genetic message from DNA to protein synthesizing machinery of cell | 2 | |
11742706056 | Translation | -synthesis of polypeptide -occurs under direction of mRNA -change in language-cell must translate base sequence of mRnA molecule into amino acid sequence of polypeptide -occurs in cytoplasm | 3 | |
11742706057 | Ribosomes | -sites of translation -complex particles that facilitate orderly linking of amino acids into polypeptide chains | 4 | |
11742706058 | Primary Transcript | initial RNA transcript from any gene, including those coding for RNA that is not translated into protein | 5 | |
11742706059 | Triplet Code | genetic instructions for polypeptide chain written in DNA as series of non-overlapping, 3 nucleotide words | 6 | |
11742706060 | Template Strand | DNA strand that provides pattern/template for sequence of nucleotides in RNA transcript | 7 | |
11742706061 | Codons | mRNA base triplets written 5'-3' direction | 8 | |
11742706062 | Reading Frame | grapings w/ symbols w/ message that needs to be translated to written language | 9 | |
11742706063 | RNA Polymerase | -pries 2 strands of DNA apart -joins RNA nucleotides as they base pair along DNA template -assemble polynucleotides 5' -> 3' -can start chain from scratch-no primer needed | 10 | |
11742706064 | Promoter | DNA sequence where RNA polymerase attaches and initiates transcription | 11 | |
11742706065 | Terminator | sequence that signals end of transcription in bacteria | 12 | |
11742706066 | Transcription Unit | stretch of DNA transcribed into RNA molecule | 13 | |
11742706067 | Transcription Factors | proteins that mediate binding of RNA polymerase and initiation of transcription | 14 | |
11742706068 | Transcription Initiation Complex | complex of transcription factors and RNA polymerase II bound to promoter | 15 | |
11742706069 | TATA Box | crucial promoter DNA sequence | 16 | |
11742706070 | RNA Processing | enzymes in eukaryotic nucleus modify pre-mRNA in specific ways before genetic messages dispatched to cytoplasm | 17 | |
11742706071 | 5' Cap | modified form of guanine added onto 5' end after transcription 1. facilitates export of mature mRNA from nucleus 2. helps protect mRNA from degradation by hydrolytic enzymes 3. helps ribosomes attach to 5' end of mRNA once mRNA reaches cytoplasm | 18 | |
11742706072 | poly-A Tail | -50-250 more A nucleotides added to 3' end by enzyme 1. facilitates export of mature mRNA from nucleus 2. helps protect mRNA from degradation by hydrolytic enzymes 3. helps ribosomes attach to 5' end of mRNA once mRNA reaches cytoplasm | 19 | |
11742706073 | RNA splicing | removal of large portions of RNA molecule initially synthesized | 20 | |
11742706074 | Introns | noncoding segments of nucleic acid that lie between coding regions | 21 | |
11742706075 | Exons | nucleotide regions that are expressed, usually translated into amino acid sequences | 22 | |
11742706076 | Spliceosome | interacts w/ certain sites along introns, releasing intron and joining together 2 exons that flanked intron | 23 | |
11742706077 | Ribozymes | RNA molecules that function as enzymes, can b/c: 1. RNA single stranded, region of RNA molecule may base-pair w/ complementary region elsewhere in same molecule-gives molecule particular 3D structure-essential to catalytic function of ribozymes, just like in enzymatic proteins 2. some RNA bases have functional groups that may participate in catalysis 3. ability of RNA to hydrogen bond w/ other nucleic acid molecules-adds specificity to catalytic activity | 24 | |
11742706078 | Alternative RNA Splicing | many genes can give rise to 2+ polypeptides, depending on which segments are treated as exons during RNA processing -# different protein products > # genes | 25 | |
11742706079 | Domains | functional regions part of protein architecture | 26 | |
11742706080 | Transfer RNA (tRNA) | transfer amino acids from cytoplasmic pool of AA to ribosome | 27 | |
11742706081 | Anticodon | nucleotide triplet that base pairs of complementary codon of mRNA | 28 | |
11742706082 | Aminoacyl tRNA Synthetases | -able to bind to different tRNAs that code for specific amino acid -catalyzes covalent attachment to tRNA -> aminoacyl tRNA released from enzyme -available to deliver AA to growing polypeptide chain of ribosome | 29 | |
11742706083 | Wobble | flexible base pairing at codon position | 30 | |
11742706084 | Ribosomal RNA (rRNA) | made in nucleolus, make up ribosomal subunits | 31 | |
11742706085 | P Site (peptidyl-tRNA site) | holds tRNA carrying growing polypeptide chain | 32 | |
11742706086 | A Site (aminoacyl-tRNA site) | holds tRNA carrying next AA to be added in chain | 33 | |
11742706087 | E Site (exit site) | where discharged tRNAs leave ribosome | 34 | |
11742706088 | Release Factor | protein that binds to stop codon @ A site | 35 | |
11742706089 | Polyribosomes | -strings of ribosomes trailing along mRNA -enables cells to make many copies of polypeptide quickly | 36 | |
11742706090 | Signal Peptide | -targets protein to ER -marks if polypeptide of proteins destined for endomembrane system or for secretion | 37 | |
11742706091 | Signal Recognition Particle (SRP) | brings ribosome to receptor protein into ER membrane | 38 | |
11742706092 | Signal Mechanism for Targeting Proteins to ER | 1. polypeptide synthesis begins on free ribosome in cytosol 2. SRP binds to signal peptide, halting synthesis momentarily 3. SRP binds to receptor proteins in ER membrane (receptor is part of protein complex w/ membrane and signal cleaving enzyme) 4. SRP leaves, and polypeptide synthesis resumes w/ simultaneous translocation across membrane (signal peptide stays attached to translocation complex) 5. signal cleaving enzyme cuts off signal peptide 6. rest of complexed polypeptide leaves ribosome and folds into final conformation | 39 | |
11742706093 | Mutations | -change into genetic information of cell -responsible for huge diversity of genes found along organisms | 40 | |
11742706094 | Point Mutations | -chemical changes in a single base pair of a gene -if occurs in a gamete, can be transmitted to offspring and future generations | 41 | |
11742706095 | Base Pair Substitutions | replacement of one nucleotide and its partner w/ another pair of nucleotides | 42 | |
11742706096 | Missense Mutations | -change one amino acid to another -new amino acid may have properties similar to replaced amino acid, or may be in region where exact sequence of amino acids not essential to proteins functions | 43 | |
11742706097 | Nonsense Mutation | -change codon for amino acid into stop codon -causes translation to be terminated prematurely -resulting polypeptide shorter than polypeptide encoded by normal gene | 44 | |
11742706098 | Insertions | additions of nucleotide pairs in gene | 45 | |
11742706099 | Deletion | losses of nucleotide pairs in gene | 46 | |
11742706100 | Frameshift Mutations | -# nucleotides inserted/deleted NOT multiple of 3 -may alter reading frame of genetic message | 47 | |
11742706101 | Mutagen | physical and chemical agents that interact w/ DNA that cause mutations | 48 | |
11742706102 | rRNA | makes up 60% of the ribosome; site of protein synthesis | 49 | |
11742706103 | gene | equals one RNA molecule | 50 | |
11742706104 | snRNA | small nuclear RNA | 51 | |
11742706105 | srpRNA | signal recognition particle that binds to signal peptides | 52 | |
11742706106 | RNAi | Interference RNA | 53 | |
11742706107 | ribozyme | RNA molecule that functions as an enzyme | 54 |