Given below is the DNA coding sequence. Its complementary strand would read as:
5'-GTATTACG-3'
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 3'-CATAATGC-5'
The complementary strand of a DNA sequence is formed by pairing the nitrogenous bases according to base-pairing rules:
- A (Adenine) pairs with T (Thymine)
- T (Thymine) pairs with A (Adenine)
- G (Guanine) pairs with C (Cytosine)
- C (Cytosine) pairs with G (Guanine)
Now, for the given DNA coding sequence 5'-GTATTACG-3', its complementary strand:
- G pairs with C
- T pairs with A
- A pairs with T
- T pairs with A
- T pairs with A
- A pairs with T
- C pairs with G
- G pairs with C
Thus, the complementary strand reads as: 3'-CATAATGC-5'