Fig. 16-1

Fig Living S cells (control) Living R cells (control) Heat-killed S cells (control) Mixture of heat-killed S cells and living R cells Mouse dies Mouse healthy Living S cells RESULTS EXPERIMENT

Fig Bacterial cell Phage head Tail sheath Tail fiber DNA 100 nm

Fig EXPERIMENT Phage DNA Bacterial cell Radioactive protein Radioactive DNA Batch 1: radioactive sulfur ( 35 S) Batch 2: radioactive phosphorus ( 32 P)

Fig EXPERIMENT Phage DNA Bacterial cell Radioactive protein Radioactive DNA Batch 1: radioactive sulfur ( 35 S) Batch 2: radioactive phosphorus ( 32 P) Empty protein shell Phage DNA

Fig EXPERIMENT Phage DNA Bacterial cell Radioactive protein Radioactive DNA Batch 1: radioactive sulfur ( 35 S) Batch 2: radioactive phosphorus ( 32 P) Empty protein shell Phage DNA Centrifuge Pellet Pellet (bacterial cells and contents) Radioactivity (phage protein) in liquid Radioactivity (phage DNA) in pellet

Fig Sugar–phosphate backbone 5 end Nitrogenous bases Thymine (T) Adenine (A) Cytosine (C) Guanine (G) DNA nucleotide Sugar (deoxyribose) 3 end Phosphate

Fig (a) Rosalind Franklin (b) Franklin’s X-ray diffraction photograph of DNA

Fig. 16-6a (a) Rosalind Franklin

Fig. 16-6b (b) Franklin’s X-ray diffraction photograph of DNA

Fig (c) Space-filling model Hydrogen bond 3 end 5 end 3.4 nm 0.34 nm 3 end 5 end (b) Partial chemical structure(a) Key features of DNA structure 1 nm

Fig. 16-7a Hydrogen bond 3 end 5 end 3.4 nm 0.34 nm 3 end 5 end (b) Partial chemical structure(a) Key features of DNA structure 1 nm

Fig. 16-7b (c) Space-filling model

Fig. 16-UN1 Purine + purine: too wide Pyrimidine + pyrimidine: too narrow Purine + pyrimidine: width consistent with X-ray data

Fig Cytosine (C) Adenine (A)Thymine (T) Guanine (G)

Fig A T G C TA TA G C (a) Parent molecule

Fig A T G C TA TA G C A T G C T A T A G C (a) Parent molecule (b) Separation of strands

Fig A T G C TA TA G C (a) Parent molecule AT GC T A T A GC (c) “Daughter” DNA molecules, each consisting of one parental strand and one new strand (b) Separation of strands A T G C TA TA G C A T G C T A T A G C

Fig Parent cell First replication Second replication (a) Conservative model (b) Semiconserva- tive model (c) Dispersive model

Fig EXPERIMENT RESULTS CONCLUSION Conservative model Semiconservative model Dispersive model Bacteria cultured in medium containing 15 N Bacteria transferred to medium containing 14 N DNA sample centrifuged after 20 min (after first application) DNA sample centrifuged after 40 min (after second replication) More dense Less dense Second replicationFirst replication

Fig a EXPERIMENT RESULTS Bacteria cultured in medium containing 15 N Bacteria transferred to medium containing 14 N DNA sample centrifuged after 20 min (after first application) DNA sample centrifuged after 20 min (after second replication) Less dense More dense

Fig b CONCLUSION First replicationSecond replication Conservative model Semiconservative model Dispersive model

Fig Origin of replication Parental (template) strand Daughter (new) strand Replication fork Replication bubble Two daughter DNA molecules (a) Origins of replication in E. coli Origin of replicationDouble-stranded DNA molecule Parental (template) strand Daughter (new) strand Bubble Replication fork Two daughter DNA molecules (b) Origins of replication in eukaryotes 0.5 µm 0.25 µm Double- stranded DNA molecule

Fig a Origin of replication Parental (template) strand Daughter (new) strand Replication fork Replication bubble Double- stranded DNA molecule Two daughter DNA molecules (a) Origins of replication in E. coli 0.5 µm

Fig b 0.25 µm Origin of replicationDouble-stranded DNA molecule Parental (template) strand Daughter (new) strand Bubble Replication fork Two daughter DNA molecules (b) Origins of replication in eukaryotes

Fig Topoisomerase Helicase Primase Single-strand binding proteins RNA primer

Fig A C T G G G GC CC C C A A A T T T New strand 5 end Template strand 3 end 5 end 3 end 5 end 3 end Base Sugar Phosphate Nucleoside triphosphate Pyrophosphate DNA polymerase

Fig Leading strand Overview Origin of replication Lagging strand Leading strandLagging strand Primer Overall directions of replication Origin of replication RNA primer “Sliding clamp” DNA poll III Parental DNA

Fig a Overview Leading strand Lagging strand Origin of replication Primer Overall directions of replication

Fig b Origin of replication RNA primer “Sliding clamp” DNA pol III Parental DNA

Fig Overview Origin of replication Leading strand Lagging strand Overall directions of replication Template strand RNA primer Okazaki fragment Overall direction of replication

Fig a Overview Origin of replication Leading strand Lagging strand Overall directions of replication 1 2

Fig b1 Template strand

Fig b2 Template strand RNA primer

Fig b3 Template strand RNA primer Okazaki fragment

Fig b4 Template strand RNA primer Okazaki fragment

Fig b5 Template strand RNA primer Okazaki fragment

Fig b6 Template strand RNA primer Okazaki fragment Overall direction of replication

Fig Overview Origin of replication Leading strand Lagging strand Overall directions of replication Leading strand Lagging strand Helicase Parental DNA DNA pol III PrimerPrimase DNA ligase DNA pol III DNA pol I Single-strand binding protein

Table 16-1

Fig Nuclease DNA polymerase DNA ligase

Fig Ends of parental DNA strands Leading strand Lagging strand Last fragment Previous fragment Parental strand RNA primer Removal of primers and replacement with DNA where a 3 end is available Second round of replication New leading strand New lagging strand Further rounds of replication Shorter and shorter daughter molecules

Fig µm

Fig a DNA double helix (2 nm in diameter) Nucleosome (10 nm in diameter) Histones Histone tail H1 DNA, the double helixHistones Nucleosomes, or “beads on a string” (10-nm fiber)

Fig b 30-nm fiber Chromatid (700 nm) LoopsScaffold 300-nm fiber Replicated chromosome (1,400 nm) 30-nm fiber Looped domains (300-nm fiber) Metaphase chromosome

Fig RESULTS Condensin and DNA (yellow) Outline of nucleus Condensin (green) DNA (red at periphery) Normal cell nucleus Mutant cell nucleus

Fig. 16-UN2 Sugar-phosphate backbone Nitrogenous bases Hydrogen bond G C A T G G G A A A T T T C C C

Fig. 16-UN3 DNA pol III synthesizes leading strand continuously Parental DNA DNA pol III starts DNA synthesis at 3 end of primer, continues in 5  3 direction Lagging strand synthesized in short Okazaki fragments, later joined by DNA ligase Primase synthesizes a short RNA primer

Fig. 16-UN4

Fig. 16-UN5