A. The sequence of bases in one DNA strand is given below. Identify the complementary sequence of bases in the other strand of DNA.
1.
А A
с
T
С
T
G
C
с
А
T​

The complementary sequence of bases in the complementary strand of the given single DNA strand AACTCTGCCAT will be:

TTGAGACGGTA

Explanation:

The primary structure of DNA is a double-stranded helix of nucleotides linked to each other by phosphodiester linkages. The two strands of the DNA molecule is complementary to each other. While one strand is linked in the 3' to 5' direction, the other strand is linked in the 5' to 3' direction. The two strands are held together by hydrogen bonds between the nucleotides of the two strands and this is known as base pairing. In base pairing, adenine nucleotide, A, on one strand forms two hydrogen bonds with thymine nucleotdie, T, in the other strand. Also, guanine nucleotide, G, in one strand, forms three hydrogen bonds with cytidine nucleotide, C, in the complementary strand.

Therefore, once the nucleotide sequence of one DNA strand is known, the nucleotide sequence of the complementary strand can easily be deduced.

The complementary sequence of bases in the complementary strand of the given single DNA strand AACTCTGCCAT will be: TTGAGACGGTA