AP Biology - Transcription & Translation Flashcards
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| 8715223466 | What is transcription and where does it occur? | DNA to RNA, in the nucleus | 0 | |
| 8715223467 | Composition of RNA? | Ribose sugar, N-Base, single stranded... Less stable than DNA | 1 | |
| 8715223468 | Template Strand | Transcribed DNA strand, has directions | 2 | |
| 8715223469 | Coding Strand | un-transcribed DNA strand, identical in sequence but T's are U's | 3 | |
| 8715223470 | Which direction is RNA built? | 5' to 3' | 4 | |
| 8715223471 | What direction does RNA polymerase move? | 3' to 5' | 5 | |
| 8715223472 | RNA Polymerase 1 | makes rRNA (ribosomes) | 6 | |
| 8715223473 | RNA Polymerase 2 | makes mRNA | 7 | |
| 8715223474 | RNA Polymerase 3 | makes tRNA | 8 | |
| 8715223475 | What do RNA polyermerase 1, 2, and 3 all have in common? | Each has a specific promoter sequence it recognizes | 9 | |
| 8715223476 | Initiation (Transcription) | First step of transcription. RNA polymerase binds to promoter of template strand of DNA | 10 | |
| 8715223477 | Promoter | binding site before beginning of gene | 11 | |
| 8715223478 | Transcription Factors | proteins that bind too promoter region of DNA, turned ON or OFF by controlling RNA polymerase (binding or not) | 12 | |
| 8715223479 | Elongation (Transcription) | Second step in transcription. RNA polymerase adds complimentary RNA nuclotides in 5' to 3' direction | 13 | |
| 8715223480 | Termination (Transcription) | Third step in transcription. Termination sequence cause polymerase to detach from DNA, mRNA is released | 14 | |
| 8715223481 | Exons | the real gene | 15 | |
| 8715223482 | Introns | "junk", doesn't code for proteins... viruses & proteins | 16 | |
| 8715223483 | Post Transcriptional Processing | 1.) mRNA splicing: cut out introns, paste together exons (can't have errors) 2.) Protect mature mRNA, add cap and tail | 17 | |
| 8715223484 | Primary Transcript | pre-mRNA | 18 | |
| 8715223485 | Spilceosome | Enzyme, made of snRNPs... recognize sequence, cut and paste exons together | 19 | |
| 8715223486 | Protecting mature mRNA | Enzymes in cytoplasm attack mRNA. Add 5' GTP cap & poly-A tail on 3' end | 20 | |
| 8715223487 | mRNA survival | Longer tail > Longer mRNA survial = produce more protein | 21 | |
| 8715223488 | Codon | 3 nucleotides (3 bases) = 1 polypeptide protein 3rd base isn't too important, "wobble" Codes for all life | 22 | |
| 8715223489 | How does mRNA code for proteins? | 4 different nucleotides can code for 20 different amino acids | 23 | |
| 8715223490 | How do codons match to amino acids? | tRNA = transfer RNA, attached amino acid on 3' | 24 | |
| 8715223491 | Aminoacytl tRNA synthase | Enzyme that bonds amino acid to tRNA, very unstable bond, requires ATP | 25 | |
| 8715223492 | Ribosomes | Facilitate coupling of tRNA anticodon to mRNA codon | 26 | |
| 8715223493 | A Site | Holds tRNA carrying next amino acid to be added to chain (3rd) | 27 | |
| 8715223494 | P Site | holds tRNA carrying growing polypeptide chain (2nd) | 28 | |
| 8715223495 | E Site | exit site, empty tRNA leaves ribosomes from exit site | 29 | |
| 8715223496 | Initiation (Translation) | mRNA, small and large ribosome sub-unit and tRNA come together | 30 | |
| 8715223497 | Elongation (Translation) | Polypeptide increases in length, tRNA enters A site & bonds form between amino acids | 31 | |
| 8715223498 | Termination (Translation) | Release factor binds to stop codon on mRNA, polypeptide set free and forms 3D shape, ribosomes dissociate (aren't specific, ribsomes are general) | 32 | |
| 8715223499 | Polysomes | Many ribosomes are translating at the same time | 33 | |
| 8715223500 | Prokaryote Protein Synthesis | DNA in cytoplasm, not compartmentalized, transcription and translation occur simultaneously, circular chromosome, no introns | 34 | |
| 8715223501 | Eukaryotic Protein Synthesis | DNA in nucleus, compartmentalized, transcription and translation happen separate, linear chromosomes, DNA wound on histone proteins, introns and exons | 35 | |
| 8715223502 | Translation Protein Modification | Proteins begin to fold into primary, secondary, and tertiary structure. Additional proteins, sugars, lipids, phosphate groups, ect... are added to make it functional | 36 | |
| 8715223503 | Free ribosomes | Proteins that stay in the cytoplasm | 37 | |
| 8715223504 | Bound ribosomes | (bound to ER) make proteins for golgi, ER, lysosomes, and secreted out of cell | 38 | |
| 8715223505 | Signal Recognition Protein | Brings complex to "address", similar to zip code | 39 | |
| 8715223506 | Why do eukaryotic genes regulate themselves? | Control gene expression to maintain homeostasis, can occur in any step in the pathway from gene to functional protein | 40 | |
| 8715223507 | Chromatin structure (1) | Chromatin (loosely coiled DNA) wrapped around histones (proteins) | 41 | |
| 8715223508 | Heterochromatin | Tightly wrapped around histones, NO transcription, genes turned OFF | 42 | |
| 8715223509 | Acetylation of histones | Unwinds DNA, adds actyl group- changes shape = genes turned ON | 43 | |
| 8715223510 | Methylation of DNA | Blocks transcription factors (add methyl group), no transcription = genes turned OFF, almost permanent inactivation of genes | 44 | |
| 8715223511 | Epigenetic Inheritance | inheritance of traits not directly involving nucleotide sequence | 45 | |
| 8715223512 | Transcriptional Control (2) | Most critical control of DNA, promoter, binding of RNA polymerase and transcriptional factors | 46 | |
| 8715223513 | Enhancer/Activator | Distant control sequences on DNA... binding of activator proteins | 47 | |
| 8715223514 | Transposons | Specific DNA sequences that can move w/ in and between chromosomes - can alter gene expression (usually decrease) | 48 | |
| 8715223515 | Post Transcriptional Control (3) | Alternate RNA splicing- variable processing of exons creates a variety of mature mRNA and therefore proteins | 49 | |
| 8715223516 | RNA interference | RNAi or small interferring RNA (siRNA) - short segments of double stranded RNA... death tag | 50 | |
| 8715223517 | Translational Control (4) | Blocks initiation of translation stage | 51 | |
| 8715223518 | Post Translational Control (5) | Final opportunity to control gene expression | 52 | |
| 8715223519 | Bacteria Metabolism | Bacteria need to respond quickly to changes in their new environment... if they have enough of a product they need to stop production | 53 | |
| 8715223520 | Feedback inhibition | Product acts as an allosteric inhibitor of 1st enzyme in pathway (binds, change activation site) still wasteful production | 54 | |
| 8715223521 | Prokaryotic Gene Regulation | Block transcription of genes for all enzymes in pathway... genes turned ON or OFF | 55 | |
| 8715223522 | Operon | Genes grouped together w/ related functions | 56 | |
| 8715223523 | Operator | DNA binding site that controls access of RNA polymerase to the genes | 57 | |
| 8715223524 | How do you turn genes OFF? | Repressor protein (negative control), block transcription | 58 | |
| 8715223525 | trp Operon | Repressible Operon. Makes tryptophan (amino acid), turned on when needed | 59 | |
| 8715223526 | What happens when excess tryptophan is present? | Binds to trp repressor protein and triggers repressor to bind to operator | 60 | |
| 8715223527 | Lac operon | Inducible operon. Normally turned off until needed. Digests lactose. | 61 | |
| 8715223528 | What happens when lactose is present? | Binds to lac repressor protein and triggers repressor to release DNA (induces transcription of enzymes for lactose metabolism) | 62 | |
| 8715223529 | Positive Regulation (Activators) | Bacteria prefers to break down glucose, must make sure lac operon is turned on ONLY when glucose is absent | 63 | |
| 8715223530 | What happens when glucose is absent? | Cyclic AMP accumulates, binds to CAP which then binds to DNA | 64 | |
| 8715223531 | Is lac on or off when... lactose and glucose is present? | OFF because glucose is chosen before lactose. No cAMP, cant bind to CAP, stops RNA polymerase from binding | 65 | |
| 8715223532 | Lac on or off when... lactose and glucose aren't present? | OFF because repressor is on | 66 | |
| 8715223533 | Lac on or off when... No lactose, but glucose? | OFF because it wants glucose, less cAMP = no cap... poly. can't bind | 67 | |
| 8715223534 | Lac on or off when... lactose, no glucose? | ON because repressor is off... cAMP > CAP > poly. can bind | 68 |