Which of the following combinations of base pairs will be found in a molecule of DNA?

Question

A + C = G + T
G + C = T + A
A = G and C = T
A = C

Answer 1

In a molecule of DNA, the base pairing follows specific rules known as Chargaff's rules, where adenine (A) pairs with thymine (T), and guanine (G) pairs with cytosine (C).

Given the options:

1. A + C = G + T - This is incorrect. There is no proper pairing between A and C or G and T in DNA.

2. G + C = T + A - This is incorrect. The correct pairs are G with C and A with T; they don't equal each other in this way.

3. A = G and C = T - This is incorrect since A and G (both purines) are not equal, nor are C and T (a pyrimidine).

4. A = C - This statement is also incorrect since adenine (A) and cytosine (C) are different bases and do not equal each other.

None of the provided combinations accurately reflect the base pairing rules found in DNA. The correct pairing is:

• A pairs with T (A = T)
• G pairs with C (G = C)

So all provided options are incorrect.