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Nucleic Acids
· DNA-deoxyribonucleic acid
· RNA-ribonucleic acids
Messenger RNA
- +RNA : (^) transfer RNA
- rRNA : (^) ribosomal RNA DNA Transform Bacteria
- Frederick th
develop vaccine^ for^ premonia
- 2 strains · Pathogenic (disease (^) causing)- S · Non-Pathogenic(harmless) - R
- pathogenic /heat + (^) non (^) pathogenic= (^) pathogenic ↓ Living S^ Cells^ Living^
R cells heat killed s cells heat killed S + R
control control^ control ↓
pathogenic
non pathogenic ↓
morse
↓ mouse↓^ mouse^ died
mouse lived live d
died
*transformation occured - change in geneotype + phenotype dueto
assimilation of^ external^ DNA (^) by a cell Viruses-bacteriophages^ & or^ phages) (^) simpler than^ cells · viruses infect bacterial cells to (^) spread · more than DNA or RNA (^) enclosed (^) by PRO
Hershey Chase Is PRO^ or^ DNA^ the^ genetic material of (^) phage T
- T (^2) (virus) (^) comes into contact W/ E. Coli cell-inserts its DNA to (^) make T2 (^) cells * - Trus A - 2 · - small intestine ⑤ (^2)
& ⑭ E^.^ Coli ·. : bacterials en (^) TEDNA more T · o
produced
Experiment Batch 1 :^ RadioactiveSulfer (359)^
isotope
in phage PRO
↑ T *^ ② ↓ Jj-liquid I C^ ~^ 'sc^ - Cell^ ⑭- -^ cell^
*pellet
1 4.^ Phage
labeled phages 2.^ agitation separates 3. centrifuged cells^ PRO found in
infect cell The^ phages from^ the^ form^ a^ pellet eiguid
cell Batch 2 : (^) Radioactive (^) Phosphorous (P) (^) in (^) phage DNA 4 Y^ ②
-^ I C n.^ -^
~ 'sc -^ Cell^ S 4.^ phage^ DNA
1 was^ found^ in
labeled phages 2.^ agitation separates 3. centrifuged cells^ the pellet
infect (^) cell The^ phages from^ the^ form^ a^ pellet cell Results
-PRO remained outside of cell
- DNA found (^) inside (^) the cell
* DNA functions as genetic of phage T
Nitrogenous Bases Adenine - Thyamine w 32 % Citosine -^ Guanine ~1%
(^3) models of (^) DNA (^) Replication Conservative :^ parent strands^ rejoin after^ copying Semi Conservative :^ one^ molecule is (^) /parent -^1 complement Dispersive:^ each^ new^ strand^ contains^ both^ parent-^ copy T
Meselson -^ Stahl^ zu
inn · (^) cultured E. (^) Coli
- heavy isotope : "N (^) nu -^ u lighter isotope^ :^ "N^ n^ N
*DNA :^ Semi conservative
E tracked (^) density of^ parent t^ daughter DNA strand^ ,^ found^ some^ of^ each Ye of^ P 2 of^ d^ = (^) Semi cons. Vocab
Helicase :^ unwinds separates parental DNA strands
Single Stranded^ Binding Pro.:^ Stableizes unwound^ parental strands Topoisomerase:^ break, swivels -^ rejoins parental DNA^ ahead^ of replication fork^ relieving strain replication RNA Primer:^ short (^) chain of (^) RNA/signals start (^) here-enzyme (^) begin Primase :^ the (^) enzyme that adds (^) RNA (^) primers using the (^) parental PNA
as a template
DNA (^) Ligase:^ Jews (^) together all (^) new (^) fragments of (^) DNA DNA (^) Polymerase: (^) takes over after RNA is added (adds (^) nucleotides
1. replaces DNA primer with DNA
3 .MAIN^ polymerase to^ add^ more^ nucleotides^ to^ build^ complementary chain
