Question

1. Post transcriptional modification of RNA by addition of nucleotides that are not encoded in the DNA sequence occurs for some RNA products. Which of the following is correct pairing of RNA product and modification?

A. tRNA - CCA added to 3' end

B. mRNA - CCA added to 3' end

C. rRNA - poly A added to 3' end

mRNA - 7meG added to 3' end

2. Predict the mRNA sequence that is encoded by the DNA sequence shown in the figure:

DNA: sense: GTACGTCTAGCTACACA

         antisense: CATGCAGTACGATGTGT

A. CATGCAGTACGATGTGT

B. CAUGCAGUACGAUGUGU

C. GTACGTCTAGCTACACA

D. GUACGUCUAGCUACACA

E. ACACATCGATCTGCATG

F. ACACAUCGAUCUGCAUG

Answer 1

1. tRNA- CCA added to the 3' end. All mature tRNAs carry the invariable sequence CCA at their 3′ end

2. The production of mRNA off of a DNA template, called transcription, is similar to DNA replication. First, the two DNA strands will separate from each other. Next, RNA nucleotides will come in and base pair with the corresponding DNA nucleotide on just one strand of DNA, called the template strand. In the place of A, U is placed in RNA sequence. The rest of the sequence is just the complimentary of the template strand

DNA sense strand : GTACGTCTAGCTACACA

mRNA : B. CAUGCAGAUCGAUGUGU