15.4 RNA Processing in Eukaryotes

Question 1

RNA editing

Answer 1

direct alteration of one or more nucleotides in
an mRNA that has already been synthesized

Question 2

7-methylguanosine cap

Answer 2

modification added to the 5’ end of
pre-mRNAs to protect mRNA from degradation and
assist translation

Question 3

poly-A tail

Answer 3

modification added to the 3’ end of pre-mRNAs
to protect mRNA from degradation and assist mRNA
export from the nucleus

Question 4

exons

Answer 4

correspond to protein-coding sequences (ex-on signifies that they are
expressed)

Question 5

introns

Answer 5

intervening sequences , (int-ron denotes their intervening role), which may be involved in gene
regulation but are removed from the pre-mRNA during processing

Question 6

splicing

Answer 6

The process of removing introns and reconnecting exons

Question 7

anticodon

Answer 7

three-nucleotide sequence in a tRNA molecule
that corresponds to an mRNA codon