Identify the sequence of bases of m-RNA molecule synthesised on the given strand of DNA AGCGATTAC.
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → UCGCUAAUG.
In transcription, mRNA is synthesized using a DNA template strand. The rules of base pairing are:
Adenine (A) pairs with Uracil (U) in RNA (instead of Thymine (T) in DNA),
Thymine (T) pairs with Adenine (A),
Cytosine (C) pairs with Guanine (G), and
Guanine (G) pairs with Cytosine (C).
The given DNA strand is:
\(\text{DNA: } 5' - AGCGATTAC - 3'\)
Steps for transcription:
Pair the complementary RNA bases with the DNA template:
- A → U
- G → C
- C → G
- G → C
- A → U
- T → A
- T → A
- A → U
- C → G
Thus, the sequence of bases on the mRNA will be:
\(\text{mRNA: } 5' - UCGCUAAUG - 3'\)
Conclusion:
The correct sequence of the mRNA molecule synthesized is: option (3): UCGCUAAUG.