Question

1. which would be the mrna transcribed from parent strand 1? a. ugguacgca b. tggtacgca c. accaugcgu d. accatgcgt e. none of the above

Explanation:

Step1: Recall base - pairing rules in transcription

In transcription, DNA is transcribed into mRNA. DNA has bases A, T, C, G and mRNA has bases A, U, C, G. 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. Also, mRNA is synthesized in the 5' - 3' direction.

Step2: Analyze the options

Option b and d have 'T' which is a DNA - specific base, so they can be excluded. Option a has the wrong complementary sequence. The correct complementary sequence to a DNA strand for mRNA is formed by applying the base - pairing rules. If we assume the DNA strand has a sequence complementary to the correct mRNA, the correct mRNA sequence based on base - pairing is c. A C C A U G C G U.

Answer:

C. A C C A U G C G U