Question

6.The snRNAs play a dual role during splicing, recognizing specific sequences that dictate the the branching and splicing sites and catalyzing the splicing reaction directly.

7.______ is (are) so extensively modified post-transcriptionally that more than 10% of all nucleotides in the mature molecule(s) are altered to yield modified nucleotides

8. A process called alternative splicing can produce mRNAs with _______ from the same gene

Answer 1

6.True

snRNPs have three roles in splicing:

1. Recognition of the 5’ splice site and the branch site
2. Bringing these sites together as required
3. Catalyze or help to catalyze the RNA cleavage & joining reaction.

7. d. tRNA.

tRNAs have additional bases: ribothymine, pseudouridine, dihydrouridine and many others (the first three specific bases are created from the modification of uracil)

8. a. Variable number of exons out of a pre-determined number of exons.