DNA StructureDouble Stranded = Double HelixSugar – DeoxyriboseBase PairsA / T pair - 2 hydrogen bondsG / C pair (in RNA G / U) - 3 hydrogen bonds – stronger pairAdenine and Guanine = purines (2 nitrogenous rings)Thymine, Cytosine, Uracil = pyrimidines (1 nitrogenous rings)RNA StructureSingle Stranded moleculeSugar – Ribose (one more oxygen)Uracil base instead of ThiamineU / A base pairDNA ReplicationPurpose to create two complementary DNA strands1. Helicase – enzyme that breaks the hydrogen bonds of the base pairs and separates the DNA into two strands2. Replication fork- where the splitting of the DNA strand starts3. Leading Strand- top strand – 5’ to 3’RNA Primase – only needed in the beginning of the process to “prime” or fill in a section of nucleotides that was just unzipped with RNA primersDNA Polymerase – following the RNA primase to hook on, it continues to add nucleotides (base pairs) down the replication fork.Proofreading ability allows it to correct errors (mismatched bases) made during replicationCan only add strands from 5’ to 3’ sequence4. Lagging Strand- bottom strand – 3’ to 5’Has to be copied in segments – works opposite of leading strand so that goes in 5’ to 3’ direction – working backwardsRNA Primase – lays down RNA primers in segments for the DNA polymerase to followDNA Polymerase – hooks on to newly laid down nucleotides and then works down the strand continuing to add nucleotidesCan proofread and go back and correct mismatched bases made during replicationOkazaki Fragments - individual segments consisting of RNA primers of nucleotides followed by the nucleotides laid down by the DNA polymeraseDNA Polymerase - another kind of this enzyme comes along and replaces all of the RNA primersDNA Ligase – joins all of the fragmentsTranscription UnitPromoter- sequenceTATA BoxTATAAAAATATTTTHelps our enzymes figure out where to bind to the strandUpstream toward 3 prime endDownstream toward 5 prime endRNA Polymerase- copies the DNA downstream of the TATA box towards the 5 prime end- begins to unzip the DNA strandCopies it into messenger RNA (mRNA)Basic necessities come from mother’s eggSends them into the nucleus to be matchedTermination Signal- tells the RNA polymerase to pull off and stopmRNA –5’ cap- special type of guaninePoly-A tail- 3’ adds adenineRNA SplicingSnurps- Small nuclear ribonucleo proteins- a combination of RNA and proteins recognize sequences that signal the start and end of the areas to be splicedSplisosome-A combination of Snurps and other proteinsIs what actually does the editingExons- what will be spliced together and be expressedIntrons- what isn’t neededMaterial gets recycled back into nucleusTakes out the nitrogenous bases that can be reused in either DNA or RNATranslation-Processed mRNAs get fed into ribosomes in the rough endoplasmic reticulumRibosomes have binding sites that allow the mRNA to interact with the tRNA (transfer RNA/translation RNA)tRNA- translates from the language of nucleotides into the language of proteinsone end have an amino acidother end have 3 nitrogenous basesTriplet Codon- the three bases that are matched at one timeAnticodon- the bases that are matched with their opposite bases in the ribosomesAUG – finds an tRNA with anticodon on mRNAStarts of a polypeptide chain- beginning of proteinDNA StructuresPrimary structure- single bonded- sequenceSecondary Structure – sheets & spirals ( double helix)Tertiary Structure – R Group BondsDNA Structure- Double Stranded = Double Helix - Sugar – Deoxyribose - Base Pairs o A / T pair - 2 hydrogen bonds o G / C pair (in RNA G / U) - 3 hydrogen bonds – stronger pairo Adenine and Guanine = purines (2 nitrogenous rings)o Thymine, Cytosine, Uracil = pyrimidines (1 nitrogenous rings)RNA Structure- Single Stranded molecule- Sugar – Ribose (one more oxygen)- Uracil base instead of Thiamine - U / A base pair DNA Replication Purpose to create two complementary DNA strands - 1. Helicase – enzyme that breaks the hydrogen bonds of the base pairs and separates the DNA into two strands - 2. Replication fork- where the splitting of the DNA strand starts - 3. Leading Strand- top strand – 5’ to 3’ o RNA Primase – only needed in the beginning of the process to “prime” or fill in a section of nucleotides that was just unzipped with RNA primers o DNA Polymerase – following the RNA primase to hook on, it continues to add nucleotides (base pairs) down the replication fork. Proofreading ability allows it to correct errors (mismatched bases) made during replication o Can only add strands from 5’ to 3’ sequence - 4. Lagging Strand- bottom strand – 3’ to 5’ o Has to be copied in segments – works opposite of leading strand so that goes in 5’ to 3’ direction – working backwardso RNA Primase – lays down RNA primers in segments for the DNA polymerase to follow o DNA Polymerase – hooks on to newly laid down nucleotides and then works down the strand continuing to add nucleotides Can proofread and go back and correct mismatched bases made during replication o Okazaki Fragments - individual segments consisting of RNA primers of nucleotides followed by the nucleotides laid down by the DNA polymerase o DNA Polymerase - another kind of this enzyme comes along and replaces all of the RNA primerso DNA Ligase – joins all of the fragments Transcription Unito Promoter- sequence o TATA BoxT A T A A A AA T A T T T T Helps our enzymes figure out where to bind to thestrand Upstream toward 3 prime end Downstream toward 5 prime end o RNA Polymerase - copies the DNA downstream of the TATA box towards the 5 prime end- begins to unzip the DNA strand Copies it into messenger RNA (mRNA) Basic necessities come from mother’s egg Sends them into the nucleus to be matchedo Termination Signal - tells the RNA polymerase to pull off and stop o mRNA – 5’ cap - special type of guanine Poly-A tail - 3’ adds adenine - RNA Splicing o Snurps - Small nuclear ribonucleo proteins- a combination of RNA and proteins recognize sequences that signal the start and end of the areas to be splicedo Splisosome - A combination of Snurps and other proteins Is what actually does the editing Exons- what will be spliced together and be expressed Introns- what isn’t needed - Material gets recycled back into nucleus Takes out the nitrogenous bases that can
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