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| 11837937866 | Death cap mushroom | A kind of poisonous mushroom; death comes from ingesting a toxin called amanitin. | 0 | |
| 11837939635 | a-amanitin found in amanita phalloides (deathcap mushrooms) inhibits | RNA polymerase II, the enzyme that transcribes protein-encoding genes in eukaryotes Amanitin binds to RNA polymerase and jams the moving parts of the enzyme, interfering with its ability to move along the DNA template | 1 | |
| 11838017647 | Ribozymes | catalytic RNA molecules that function as enzymes and can splice RNA, and even catalyze the formation of peptide bonds between amino acids. | 2 | |
| 11838042151 | Early in biological life, RNA probably served as both, | the original genetic material and as biological catalysts | 3 | |
| 11838048461 | Differences in DNA and RNA | 1) RNA has ribose sugar, instead of deoxyribose 2) RNA contains uracil in place of thymine 3) RNA is single stranded, not double stranded RNA has a hydroxyl group on the 2' carbon atom, making RNA more reactive the DNA which has a hydrogen atom | 4 | |
| 11838066210 | Primary RNA vs secondar RNA |  | 5 | |
| 11838103924 | rRNA | ribosomal RNA; type of RNA that makes up part of the ribosome | 6 | |
| 11838104408 | mRNA | messenger RNA; type of RNA that carries instructions from DNA in the nucleus to the ribosome | 7 | |
| 11838106549 | iRNA | Interference RNA | 8 | |
| 11838108870 | pre-mRNA | precursor mRNA; the first strand of mRNA produced by gene transcription that contains both introns and exons | 9 | |
| 11838120006 | tRNA | transfer RNA; type of RNA that carries amino acids to the ribosome | 10 | |
| 11838122537 | snRNA | Found only in the nucleus of eukaryotes and functions to remove introns from mRNA known as "snurps" Converts pre-mRNA to mRNA | 11 | |
| 11838146998 | snoRNA | processing of rRNA | 12 | |
| 11838148539 | miRNA | a class of functional RNA that regulates the amount of protein produced by a eukaryotic gene Carry out iRNA, which helps to trigger the degradation of mRNA or inhibit the translation into proteins | 13 | |
| 11838161442 | piRNA | Piwi binding RNA, thought to aid in silencing of transposons during gamete production | 14 | |
| 11838161443 | crRNA | CRISPR RNA assists destruction of foreign DNA | 15 | |
| 11838167206 | lncRNA | Long non coding RNA, gene silencing (Xist in x-chromosome inactivation) | 16 | |
| 11838190117 | Pair the RNA to it's function a) snRNA b) tRNA c) miRNA d) rRNA | a) pre-mRNA to to mRNA b) help to link amino acids into a polypeptide chain c) trigger the degradation of mRNA d) makes up ribosomes | 17 | |
| 11838234831 | Three components of transcription | 1) A DNA template 2) Raw Material to build new RNA 3) The transcription apparatus, consisting of the proteins necessary for catalyzing the synthesis of RNA | 18 | |
| 11838246647 | What is transcription? | synthesis of an RNA molecule from a DNA template | 19 | |
| 11838284007 | What is the difference between the template strand and the non-template strand? | The template strand is the DNA strand that is copied into an RNA molecule, whereas the non-template strand is not copied | 20 | |
| 11838298222 | Transcription unit | Is a stretch of DNA that encodes an RNA molecule and the sequences necessary for its transcription. | 21 | |
| 11838303018 | Promoter | specific region of a gene where RNA polymerase can bind and begin transcription | 22 | |
| 11838308641 | RNA-coding region | a sequence of DNA nucleotides that is copied into an RNA molecule | 23 | |
| 11838310054 | 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 | 24 | |
| 11838319293 | Upstream and downstream is relation to transcription | The transcription apparatus is said to move downstream during transcription. It binds to the promoter (which is usually upstream of the transcription start site.) And moves toward the terminator (which is downstream of the start site) Downstream in the 5' on DNA | 25 | |
| 11838365149 | Why do molecular biologists usually write out the the sequence of the non-template strand to comepare to the RNA being transcribed? | Because the non-template strand will be the same, except the addition of uracil instead of Thymine | 26 | |
| 11838375359 | Describe the function of a promoter | Serves as a sequence to which transcription apparatus binds Determines the first nucleotide that is transcribed into RNA Determines which DNA strand is template | 27 | |
| 11838387644 | rNTPs | ribose nuceloside triphosphates used by RNA as precursors for RNA chain | 28 | |
| 11838406315 | NOTE: RNA is synthesized from ribonucleoside triphosphates. Transcription is 5-> 3: Each new nucleotide is joined to the 3-OH group of the last nucleotide added tot eh growing RNA molecule | 29 | ||
| 11838410837 | RNA polymerase | Enzyme similar to DNA polymerase that binds to DNA and separates the DNA strands during transcription consists of 5 subunits |  | 30 |
| 11838430051 | core enzyme | prokaryotic RNA polymerase consisting of α, α, β, and β' but missing σ; this complex performs elongation catalyzes the elongation of RNA by the addition of RNA nucleotides. |  | 31 |
| 11838439277 | sigma factor | controls the binding of RNA polymerase to the promoter, without sigma, RNA polymerase initiates transcription at a random point along the DNA. The addition of the sigma factor makes the core enzyme into a holoenzyme Different sigma factors bind to different promoters | 32 | |
| 11838643832 | RNA pol I | transcribes large rRNA | 33 | |
| 11838643833 | RNA pol II | Transcribes pre-mRNA, snoRNA, some meRNA, and some snRNA | 34 | |
| 11838653145 | RNA pol III | Transcribes tRNA, rRNA, and some miRNA and some snRNA | 35 | |
| 11838662250 | RNA pol IV | Found in plants, transcribe RNA that play a role in DNA methylation and chromatin structure | 36 | |
| 11838676211 | What is the function of a sigma factor? | The sigma factor controls the binding of RNA polymerase to the promoter. | 37 | |
| 11838683678 | three parts of transcription | 1. Initiation 2. Elongation 3. Termination | 38 | |
| 11838683679 | Initiation | Transcription apparatus assembles on the promoter and begins the synthesis of RNA | 39 | |
| 11838692834 | Elongation | DNA is threaded through RNA polymerase and the polymerase unwinds the DNA and adds new nucleotides, one at a time to the 3 end of the growing RNA strand | 40 | |
| 11838704631 | Termination | the recognition of the end of the transcription unit and the separation of the RNA molecule from the DNA template | 41 | |
| 11838711904 | four steps of initiation | 1) promoter recognition 2) formation of a transcription bubble 3) creation of the first bonds between rNTP's 4) escape of the transcription apparatus from the promoter | 42 | |
| 11838743122 | consensus sequence | Comprises the most commonly encountered nucleotides found at a specific location in DNA or RNA. Usually implies that the sequence is associated with an important function TATA box | 43 | |
| 11838752786 | TATA box (TATAATA) | A promoter DNA sequence crucial in forming the transcription initiation complex. also known as the pribnow box | 44 | |
| 11838771026 | upstream element | Consensus sequence found in some bacterial promoters that contains a number of A-T pairs and is found about 40 to 60 bp upstream of the transcription start site. | 45 | |
| 11838774119 | What binds to the -10 consensus sequence found in most bacterial promoters? | The holoenzyme ( core enzyme + sigma factor ) | 46 | |
| 11838792904 | Initial RNA synthesis | 47 | ||
| 11838808316 | Why do RNA molecules initially contain 3 phosphate groups at the 5' end | Initial RNA Synthesis No primer is required to initiate the synthesis of the 5 end of the RNA molecule. Two of the three phosphate groups are cleaved from each rNTP as the nucleotide is added to the 3 end of a growing RNA molecule. However, because the 5 end of the first rNTP does not take part in the formation of a phosphodiester bond, all three of it's phosphate groups remain | 48 | |
| 11838875775 | abortive initiation | Process during initiation of transcription in which RNA polymerase repeatedly generates and releases short transcripts, from 2 to 6 nucleotides in length, while still bound to the promoter. Occurs in both prokaryotes and eukaryotes. | 49 | |
| 11838885701 | transcription bubble | The site at which the double helix is unwound so that RNA polymerase can use one of the DNA strands as a template for RNA synthesis. generates + supercoiling ahead and - behind, topoisomerase helps with the stress | 50 | |
| 11838896018 | Transcriptional pausing | a temporary cessation of transcript elongation cause by backtracking | 51 | |
| 11838904065 | backtracking | disengages the 3'-OH group of the RNA molecule from the active site of RNA polymerase and temporarily halts further RNA synthesis | 52 | |
| 11838990167 | NOTE: Transcription is initiated at the transcription start site, which, in bacterial cells, is determined by the binding of RNA polymerase to consensus sequences of the promoter. No primer is required. Transcription takes place within a transcription bubble. DNA is unwound ahead of the bubble and rewound behind it. There are frequent pauses in the process of transcription | 53 | ||
| 11839058346 | Rho-independent termination of transcription | - most common - stem- loop structure (signals transcription termination): GC rich sequence (followed by several U's) with a high affinity for RNA poly, leads to formation of stem loop - Destabilizes open complex - RNA poly dissociated from DNA strand | 54 | |
| 11839060072 | Rho-dependent termination | Rho protein recognizes specific DNA sequences and causes a pause in the RNA polymerase | 55 | |
| 11839112959 | polycistronic mRNA | A group of genes that is often transcribed into a single RNA molecule | 56 | |
| 11839126888 | What characteristics are most commonly found in rho-independent terminators? | Inverted repeats followed by a string of adenine nucleotides | 57 | |
| 11839133214 | The 9 basic rules of Transcription | 58 | ||
| 11839136959 | Differences between eukaryotic and prokaryotic transcription | Eukaryotic cells possess three different RNA polymerases, each of which transcribes a different class of RNA and recognizes a different type of promoter. Thus, a genetic promoter cannot be described for eukaryotic cells; rather a promoters description depends on whether the promoter is recognized by RNA pol I, II, or III. Another difference is in the nature of promoter recognition and initiation. Many accessory proteins take part in the binding of eukaryotic RNA pol to DNA templates, and the different types of promoters require different proteins | 59 | |
| 11839185996 | How can the proteins necessary for transcription gain access to eukaryotic DNA when it is complexed with histones? | Chromatin structure is modified before transcription so that the DNA is in a more open configuration and is more accessible to the transcription machinery. | 60 | |
| 11839200603 | What helps to destabilize chromatin to make it more accessible? | acetyltransferases add acetyl groups to amino acids at the ends of the histone proteins which destabilize the nucleosome structure Chromatin remodelling proteins also can help to open up DNA | 61 | |
| 11839222730 | NOTE: The initiation of transcription in eukaryotes requires modification of chromatin structure so that DNA is accessible to the transcription machinery | 62 | ||
| 11839227383 | general transcription factors | A set of proteins that bind to the promoter of a gene whose combined action is necessary for transcription. | 63 | |
| 11839229535 | basal transcription apparatus | a group of proteins that assemble near the start site and are sufficient to initiate minimal levels of transcription | 64 | |
| 11839233592 | transcriptional activator protiens | bind to specific DNA sequences and bring about higher levels of transcription by simulating the assembly of the basal transcription apparatus at the start site. | 65 | |
| 11839242021 | Core promoter | TATA box + transcription start site |  | 66 |
| 11839247698 | regulatory promoter | DNA sequence located immediately upstream of the core promoter that affects transcription; contains consensus sequences to which transcriptional regulator proteins bind. | 67 | |
| 11839249371 | Enchancers | A segment of eukaryotic DNA containing multiple control elements, usually located far from the gene whose transcription it regulates. | 68 | |
| 11839257456 | internal promoters | Cause initiation to occur a fixed distance upstream Have a short consensus sequence located *within* the transcription unit | 69 | |
| 11839263201 | What is the difference between the core promoter and the regulatory promoter? | The regulatory promoter is farther upstream of the gene and General transcription factors bind to the core promoter; transcriptional activator proteins bind to the regulatory promoter. | 70 | |
| 11839282725 | TATA-binding protein (TBP) | A general transcription factor that binds to the TATA box and assists in attracting other general transcription factors and RNA polymerase II to eukaryotic promoters. | 71 | |
| 11839287333 | Picture of transcription initiaiton | 72 | ||
| 11839299462 | After RNA pol and general transcription factors have assembled on the core promoter... | conformational changes take place in both the DNA and the polymerase. These changes cause 11-15 bp of DNA surrounding the transcription start site to unwind, producing the single-stranded DNA that will serve as a template for transcription | 73 | |
| 11839316016 | What is the role of TFIID in transcription initiation? | TFIID binds to the TATA box and helps to centre the RNA polymerase over the transcription start site | 74 | |
| 11839365150 | How are the processes of RNA pol II termination in eukaryotes and rho-dependent termination in bacteria similar, and how are they different? | Both processes use a protein that binds to the RNA molecule and moves down the RNA toward the RNA polymerase. They differ in that rho does not degrade the RNA, whereas Rat1 does so | 75 | |
| 11870887800 | trasposons | a gene that can change its position within the genome sometimes creating reverse mutations | 76 |
