SCMA*1090 Lecture Notes - Lecture 2: Deoxyribonucleoside, Dna Gyrase, Dna Replication
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In a dna molecule a purine pairs with a pyrimidine. Explain why a-c and g-t pairs do not form: a molecule of dna was analyzed and found to contain 20% thymine. Identify which of the samples a, b and c are most likely double- stranded and which are single-stranded. 20: one strand of a dna molecule contains the nucleotide proportions 15% a, 30% t, 20% g, 35% c. Calculate the proportions of the four base pairs that would be expected in the double-stranded form of this. In a double helix, there is a complete turn every 3. 4 nm, or 10 nucleotides. The human genome contains approximately 3 billion nucleotides. Calculate how long (in metres) an average human cell"s dna would be if all chromosomes where placed end to end. Assume that the dna molecule in a particular chromosome is 75 mm long.
