Which of the following would be the first step in biosynthesis of a virus with a - (minus) strand of RNA?
A) synthesis of double- stranded RNA from a DNA template
B) synthesis of double- stranded RNA from an RNA template
C) synthesis of DNA from a DNA template
D) synthesis of DNA from an RNA template
E) transcription of mRNA from DNA

Question

Quizplus · Accepted Answer

The first step in the biosynthesis of a virus with a - (minus) strand of RNA is the synthesis of double-stranded RNA from an RNA template. This is known as the replication step in the viral life cycle. The - strand RNA serves as a template for the synthesis of the complementary + (plus) strand of RNA, which can then serve as a template for the production of viral proteins. Choice A and Choice D involve the synthesis of DNA, which is not a step in the biosynthesis of a - (minus) strand RNA virus. Choice C involves the synthesis of DNA from a DNA template, which is also not a step in the biosynthesis of an RNA virus. Choice E involves the transcription of mRNA from DNA, which is a step in the biosynthesis of a + (plus) strand RNA virus, but not a - (minus) strand RNA virus.

Which of the Following Would Be the First Step in Biosynthesis