If one strand of a DNA has the sequence ATGCTTCA, sequence of the bases in complementary strand is :
- CATTAGCT
- TACGAAGT
- ATGCGACT
- GTACTTAC
Answer
(2) TACGAAGT
Solution
Complementary base pairing: A = T (2 H-bonds), G ≡ C (3 H-bonds)
Given strand: A T G C T T C A
Complementary: T A C G A A G T
∵ every A is replaced by T, T by A, G by C and C by G ⇒ TACGAAGT
Answer: (2)