Question

“Unlike what happens in DNA replication, where both strands are copied, only one of the two strands is transcribed into mRNA. The DNA strand that contains the gene is sometimes called the sense strand, or coding strand, and the DNA strand that gets transcribed to give RNA is called the antisense strand, or noncoding strand. Because the sense strand and the antisense strand are complementary, and because the DNA antisense strand and the newly formed RNA strand are also complementary, the RNA molecule produced during transcription is a copy of the DNA sense strand… The only difference is that the RNA molecule has a U everywhere the DNA sense strand has a T.”

Consider the following segment of a DNA sense strand:

(5’) CTA-ACT-AGG-GGG-TCG-CCG (3’)

1. Determine the base sequence in the antisense (non-coding) strand. Be sure to specify which end is 5’ and which is 3’
2. Determine the base sequence in the messenger RNA strand. Be sure to specify which end is 5’ and which is 3’.
3. Determine the amino acid sequence coded by the mRNA strand
4. Specify the anticodon present on each of the transfer RNA’s involved.

Answer 1

a. the base sequence in the antisense (non-coding) strand are-

-3'-GAT-TGA-TCC-CCC-AGC-GGC-5'-

b. the base sequence in the messenger RNA strand.-

-5'- CUA-ACU-AGG-GGG-UCG-CCG-3'-

c. amino acid sequence coded by the mRNA strand.-

5- leucine- Threonine-arginine- glycine- serine- proline-3

d. anticodon present on each TRNA involved are:-

3'- GAU-UGA-UCC-CCC-AGC-GGC-5'