Question

If the sequence of the 5'-3' strand is AATGCTAC, then the complementary sequence has the following sequence: a. 3'-AATGCTAC-5' b. 3'-CATCGTAA-5' c. 3'-TTACGATG-5' d. 3'-GTAGCATT-5

Short answer

If the strand sequence is $5^{\text{'}}-3^{\text{'}}$ AATGCTAC, the corresponding sequence of $3^{\text{'}}-5^{\text{'}}$will be TTACGATG, according to DNA complementary base pairing. As a result, option is the proper response (c)

Step-by-step solution

Step:1 Introduction 

Except for a few viruses, DNA is the genetic substance of all living species. It has two polynucleotide chains made up of nucleotides made up of a nitrogenous base, a pentose sugar, and phosphoric acid that are double helical in nature.

Step:2 Correct answer

Because of the complimentary base pairing rule, if the strand sequence $5^{\text{'}}-3^{\text{'}}$is AATGCTAC, the complementary sequence will be $3^{\text{'}}-5^{\text{'}}$TTACGATG. As a result, option (c) is right.

Step:3 Justification of the correct answer

3' -TTACGATG - 5' is the option (c). DNA's two polynucleotide chains are inherently anti-parallel. One strand has orientation, while the other strand does not. Between the nitrogenous bases, these strands demonstrate complimentary base pairing. Adenine always forms two hydrogen bonds with thymine (A-T), while guanine always forms three hydrogen bonds with cytosine (G-C) (G-C). The complementary sequence of strand will be TTACGATG if the DNA strand sequence is AATGCTAC.

Step:4 Explanation of Incorrect answer

3' - AATGCTAC- 5' is the code for option (a). The complimentary strand for the sequence 5'AATGCTAC-3' cannot be this. As a result, it is an inaccurate response.

3' - CATCGTAA-5' is the code for option (b). The complimentary strand for the sequence 5'AATGCTAC-3' cannot be this. As a result, it is an inaccurate response.

3'- GTAGCATT- 5'is the code for option (d). The complimentary strand for the sequence AATGCTAC-3 cannot be this. As a result, it is an inaccurate response.

As a result, alternatives (a), (b), and (d) are wrong.