Question

You are a virologist interested in studying the evolution of viral genomes. You are studying two newly isolated viral strains and have sequenced their genomes. You find that the genome of strain 1 contains 25% A, 55% G, 20% C, and 10% T. You report that you have isolated a virus with a single-stranded DNA genome. Based on what evidence can you make this conclusion?aA. single-stranded genomes always have a large percentage of purinesB. using the formula: G - A = C + TC. Double-stranded genomes have equal amounts of A and TD. Single-stranded genomes have a higher rate of mutation

Answer 1

• Answer: Double stranded genomes have equal amounts of A and T. Explanation: In a DNA double helix, the complementary nucleotides must be equal otherwise it would cause staggering A and T must be equal to each other as C and G must be equal to each other. The base pairs need not to be in the same ratios - i.e. A-T and C-G base pairs do not have to equal each other