Question

if part of the dna gene being transcribed is tgcaat, what will the mrna code be for that part?

• tgcaat
• acguua
• ugcaau
• ucgttu

Explanation:

To determine the mRNA code from a DNA sequence, we use the base - pairing rules for transcription. In DNA, the bases are adenine (A), thymine (T), cytosine (C), and guanine (G). During transcription, DNA is used as a template to make mRNA. The base - pairing rules for transcription are: adenine (A) in DNA pairs with uracil (U) in mRNA, thymine (T) in DNA pairs with adenine (A) in mRNA, cytosine (C) in DNA pairs with guanine (G) in mRNA, and guanine (G) in DNA pairs with cytosine (C) in mRNA.

Let's analyze the given DNA sequence "TGCAAT" base by base:

• The first base of DNA is T. According to the base - pairing rule, T pairs with A in mRNA.
• The second base of DNA is G. G pairs with C in mRNA.
• The third base of DNA is C. C pairs with G in mRNA.
• The fourth base of DNA is A. A pairs with U in mRNA.
• The fifth base of DNA is A. A pairs with U in mRNA.
• The sixth base of DNA is T. T pairs with A in mRNA.

Putting these paired bases together, we get the mRNA sequence "ACGUUA".

Answer:

B. ACGUUA