1. The B-dna structure found in solution is a a right-handed double helix of antiparallel chains (11 bp/turn) B left-handed double helix of antiparallel chains (10 bp/turn) C right-handed double helix of antiparallel chains(10 bp/turn). D left-handed zig-zag helix of antiparallel chains(12 bp/turn) E right-handed double helix of parallel chains(10 bp/turn) 2. dna differs from rna in the following features a DNA is resistant to base catalyzed hydrolysis; Rna is hydrolyzed by oh b dNA residues are linked by 3 -->5 phospho lester bonds RNA is 2 -->5 linked c DNA has deoxyribose residues; RNA has ribose residues D DNA contains the a.c. g and t bases Rna contains a c.g. and u e All but the second choice are correct d ifferences 3. Because DNa is a highly charged polyanion, its stability to heat denaturation ("melting") a does not depend on hydrophobic interactions B c decreases with increasing [salt d is independent ofG +C content E increases with increasing pH 4. The total contour length of dna in a human cell is about b 1 mm C10 d 1 meter E 12 furlongs 5. Polyacrylamide and agarose gel electrophoresis separate nucleic acids based primarily on their a length B ratio of mass/charge C (G+C)(A+T)content. D organismal origi E content of N (buoyant density) 6. The number of supercoils in a covalently-closed, circular DNA can only be a at least one of the phospho ester chains is cleaved b both of the phosphodiester chains are cleaved c histones are bound to the dna d the salt concentration is increased >10 M1. The B-DNA structure found in solution is a A right-handed double helix of antiparallel chains (11 bp/turn). B left-handed double helix of antiparallel chains (~10 bp/turn). C right-handed double helix of antiparallel chains (~10 bp/turn). D left-handed zig-zag helix of antiparallel chains (12 bp/turn). E right-handed double helix of parallel chains (~10 bp/turn). 2. DNA differs from RNA in the following features A DNA is resistant to base catalyzed hydrolysis; RNA is hydrolyzed by OH- . B DNA residues are linked by 3'-->5' phosphodiester bonds; RNA is 2'-->5' linked. C DNA has deoxyribose residues; RNA has ribose residues. D DNA contains the A, C, G and T bases; RNA contains A, C, G, and U. E All but the second choice are correct differences. 3. Because DNA is a highly charged polyanion, its stability to heat denaturation ("melting"): A does not depend on hydrophobic interactions. B increases with increasing [salt]. C decreases with increasing [salt]. D is independent of G + C content. E increases with increasing pH. 4. The total contour length of DNA in a human cell is about A 1 mm. B 1 mm. C 10 cm. D 1 meter. E 12 furlongs. 5. Polyacrylamide and agarose gel electrophoresis separate nucleic acids based primarily on their A length. B ratio of mass/charge. C (G+C)/(A+T) content. D organismal origin. E content of 15N (buoyant density). 6. The number of supercoils in a covalently-closed, circular DNA can only be changed if A at least one of the phosphodiester chains is cleaved. B both of the phosphodiester chains are cleaved. C histones are bound to the DNA. D the salt concentration is increased >1.0 M