Question

DNA was extracted from E coli.The proportion of Cytosine was found to be 30%,then what will be the amount of Adenine

Answer 1

Answer:

20%

Explanation:

C=G=30%

it means that, C+G=60%

now, A+T=100-60=40%

therefore A=20%

Answer 2

Answer:

20%

Explanation:

As the given question it is from a double stranded DNA, C is always complimentary with G and A is complementary with T.

So now according to  Chargaff's rules, it states that DNA from any cell of all organisms should have a 1:1 ratio Base Pair i.e A is equals to T and G is equals to C or Purine=pyimidine . As it was stated in the above paragraph.

Now ,

Total C + G = 30% + 30% (As the formula suggests C=G)

And,

Total A + T = 100- (C+G)

=> A + T = (100 - 60) %

=> A + T = 40%

=> A = (40/2)% [ As A=T]

=> A = 20%(answer)