You have analyzed the DNA isolated from a newly discovered virus and found that its base composition is 32% A, 17% C, 32% G, and 19% T. What would be a reasonable explanation of this observation?
(a) The virus must be extraterrestrial
(b) In some viruses, double-stranded DNA is made up of base pairs containing two purines or two pyrimidines
(c) Some of the T was converted to C during the isolation procedure
(d) The genome of the phage is single-stranded not double-stranded

As the % of A is not equal (or approx) to T and that of G is not equal to C, thus the genome of the virus is single stranded.

Difficulty Level:

  • 7%
  • 21%
  • 19%
  • 54%