While a eukaryotic pre-mRNA is still being synthesized it is modified on its 5' end when
a. exon shuffling mixes mRNA pieces.
b. enzymes recognize a polyadenylation signal in the trailing RNA sequence.
c. the RNA introns are cut out by the spliceosome.
d. an enzyme adds a guanine-containing cap.
e. the RNA exons are spliced together.
D
You might also like to view...
Egg-laying mammals ____
a. hatch fully developed young from their eggs b. are monotremes c. are hairless d. are confined to South America e. bear their young into permanent pouches
Organisms that obtain their energy from producers or other consumers are
A. heterotrophs. B. autotrophs and producers. C. producers. D. heterotrophs and producers. E. autotrophs.
Bacteria use restriction enzymes to ____.
A. integrate viral DNA B. destroy viral DNA C. prevent mutation of their DNA D. copy their genes E. inhibit the expression of some of their genes
The slowest but most effective control for acid-base balance is the.
A) respiratory system. B) buffer systems in the blood. C) kidney. D) brain.