Question

If the amount of A is 30% in a strand of DNA, what will be the % of G?

Answer 1

But this rule rule is applicable only for double stranded DNA molecule. The possibility of Adenine=40% and Thymine=60% is only in single stranded DNA molecule. In the question, the DNA sample referred is a single stranded DNA. hope it helps :D

Answer 2

If the amount of adenine (A) is 30%, the amount of guanine (G) will be 20%.

Step-by-step explanation:

As we know, DNA has four nitrogenous bases: adenine (A), guanine (G), cytosine (C) and thymine (T).

These nitrogenous bases are complementary to each other, in this case, adenine binds to thymine and guanine binds to cytosine. For this connection to be carried out it is necessary that the DNA has the same amount of adenine and thymine and the same amount of cytosine and guanine.

For this reason, we can say that if DNA has 30% adenine in its composition, it also has 30% thymine in its composition. This gives a total of 60% of all DNA, which means that 40% is made up of guanine and cytosine. Therefore, guanine makes up 20% of the DNA and cytosine makes up 20%.