ch 17 Gene Expression Flashcards
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| 2000143670 | Transcription | Copying 1 strand of DNA of a gene Used as a template to make RNA | 0 | |
| 2000143671 | Transcription factors | Proteins that bind to a promoter | 1 | |
| 2000143672 | RNA Processing | only in Eukaryotes 1. Cell takes out introns 2. Makes a mature mRNA | 2 | |
| 2000143673 | Translation | making a protein using the info from the mRNA Nucleotide sequence --> protein Sequence | 3 | |
| 2000143674 | Where does protein processing happen | Rough ER and Golgi | 4 | |
| 2000143675 | Where does transcription occur in Eukaryotic cells | the Nucleus | 5 | |
| 2000143676 | What is RNA Polymerases role in transcription | Pries two strands of DNA apart and joins together RNA nucleotides complementary to DNA template strand, thus elongating RNA polynucleotide *doesnt need a primer | 6 | |
| 2000143677 | What are the three steps to transcription | Initiation Elongation Termination | 7 | |
| 2000143678 | What is initiation during transcription? | DNA strands open and RNA Polymerase begins to synthesis | 8 | |
| 2000143679 | What is elongation during transcription | Nucleotides are added to the growing chain Based on sequence of DNA (base pairing) DNA helix opens in front of RNA polymerase and closes behind it. | 9 | |
| 2000143680 | What is Termination during transcription? | "Stop sequence" is reached and the RNA polymerase falls off | 10 | |
| 2000143681 | What are specific transcription factors | Specific for one or several genes Create selectivity | 11 | |
| 2000143682 | The promoter | The sequence of DNA @ upstream (5') end of the gene *TATA box -RNA polymerase attaches here and initiates Tx. | 12 | |
| 2000143683 | Where do general tx factors bind? | The promoter | 13 | |
| 2000143684 | Termination in Prokaryotes | Termination sequenes makes RNA and RNA polymerase falls off. | 14 | |
| 2000143685 | Termination in Eukaryotes | A polyadenylation signal is passed @ 3' end of all genes | 15 | |
| 2000143686 | Polyadenylation | During RNA Processing 50-250 A's are added increases stability of RNA*** Protects the cells | 16 | |
| 2000143687 | 5' G-Cap | Protects 5'end from degredation modified form of Guanine nucleotide added to 5' end of pre-mRNA molecule | 17 | |
| 2000143688 | Exons | Coding regions---> sequence info for proteins | 18 | |
| 2000143689 | Introns | nonsense RNA- Spacers between Exons REMOVED | 19 | |
| 2000143690 | What is the role of snRPs in intron/exon splicing? | Bind to sequences of nucleotides RNA base pairs with intron snRPs bind to each other and consequently bend RNA | 20 | |
| 2000143691 | Spliceosome | formed by snRPs cuts RNA @ 3' AND 5' ends joins exons and removes introns | 21 | |
| 2000143692 | What is alternate splicing | different exons can be included/excluded from final mRNA can get more than 1 protein per 1 gene | 22 | |
| 2000143693 | Genetic Code | 3 bases at a time --> 4^3 = 64AA | 23 | |
| 2000143694 | Degeneracy | more than one codon/AA | 24 | |
| 2000143695 | Where is the wobble position | 3rd position | 25 | |
| 2000143696 | What is the start codon | AUG | 26 | |
| 2000143697 | How many possible reading frames per sequence? | 3, AUG tells ribosome which to use | 27 | |
| 2000143698 | 3 Types of RNA used in translation | 1. Ribosomal RNA 2. Messanger RNA 3. Transfer RNA | 28 | |
| 2000143699 | tRNA | Has an anti-codon base pairs with codon on mRNA Has an intramolecular base pairing that gives 3D structure @ 3' end | 29 | |
| 2000143700 | what charges tRNA | Aminoacyl tRNA Synthetase | 30 | |
| 2000143701 | Aminoacyl tRNA Synthetase | At least 1 for each AA- reads anticodon tRNA Attaches to the proper AA | 31 | |
| 2000143702 | E-Site | Exiting site uncharged tRNA | 32 | |
| 2000143703 | P-Site | Site for the peptide growing chain- still basepairs with mRNA | 33 | |
| 2000143704 | A-Site | Entry site New charged tRNA enters and base pairs with mRNA | 34 | |
| 2000143705 | Initiation stage of Translation | small ribosomal subunit grabs mRNA | 35 | |
| 2000143706 | Elongation stage of Translation | -tRNA with anticodon for the next codon enters at A-Site -Growing peptide is transferred to AA on the A-Site mRNA shifts: uncharged tRNA moves to E site then tRNA with peptide moves to P site -tRNA in E site leaves CYCLE REPEATS | 36 | |
| 2000143707 | Termination stage of Translation | mRNA moves until there is a stop codon in the A-site -a release factor binds to stop codon -another RF binds to this- hydrolyzes GTP- GDP +Pi -releases peptide from tRNA in P SITE Complex of ribosome subunits fall apart | 37 | |
| 2000143708 | Polyribosomes | Several ribosomes grab the mRNA at the same time accelerates translation | 38 | |
| 2000143709 | Signal Peptide | 6-10AA long During translation, leads to specific sequence | 39 | |
| 2000143710 | SRP | Binds to signal protein block elongation | 40 | |
| 2000173553 | Mutations | changes in DNA sequence causes changes in the RNA sequence may not always cause changes in protein | 41 | |
| 2000173554 | Point mutation | change of one base. 3 possibilities | 42 | |
| 2000173555 | Silent mutation | Doesn't change the AA because of degeneracy in code | 43 | |
| 2000173556 | Missense Mutation | changes 1 AA -May not have any effect- similar AA = similar functions -May change activity of protein (usually negative) - can be beneficial= basis of evolutionary change | 44 | |
| 2000173557 | Nonsense mutation | The mutations changes a codon into a STOP codon | 45 | |
| 2000173558 | Frameshift Mutation | Mutation that shifts the "reading" frame of the genetic message by inserting or deleting a nucleotide | 46 | |
| 2000173559 | Sources of Mutations | DNA Replication, Environmental factors, Chemical mutagens, nitrates | 47 |