Draw the base pair structure of A : T and G : C.
Here is a drawing of the base pair structure of A:T and G:C:
A:T
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T:A
G:C
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C:G
In an A:T base pair, the A (adenine) base on one strand pairs with the T (thymine) base on the other strand through two hydrogen bonds. In a G:C base pair, the G (guanine) base pairs with the C (cytosine) base through three hydrogen bonds. These base pairs form the “rungs” of the DNA “ladder,” with the sugar-phosphate backbone making up the sides of the ladder.