Question

Which of the following clusters of terms accurately describes DNA as it is generally viewed to exist in prokaryotes and eukaryotes?

double-stranded, parallel, (A + T)/C + G) = 1.0, (A + G)/(C + T) = 1.0

double-stranded, antiparallel, (A + T)/C + G) = variable, (A + G)/(C+ T) = 1.0

double-stranded, antiparallel, (A + T)/C + G) = variable, (A + G)/(C + T) = variable

single-stranded, antiparallel, (A + T)/C + G) = 1.0, (A + G)/(C + T) = 1.0

double-stranded, parallel, (A + T)/C + G) = variable, (A + G)/(C + T) = 1.0

Answer 1

Answer:

double-stranded, antiparallel, (A + T)/C + G) = variable, (A + G)/(C+ T) = 1.0

DNA is a double stranded molecule and runs in an anti parallel direction, that means that runs in opposite directions, one from 5’—> 3’ and the other from 3’ —> 5’. These strands are complementary to one another. According to Chargaff’s rule

A + G = C + T , this implies,

(A+G) / ( C+T ) = 1

But, the ratio of (A+ T) / (C + G) is variable and it varies from species to species, though, it is constant within a species.