Assertion (A): Some adult gastropods (e.g., snails) are asymmetrical. Reason (R): Torsion takes place during the development of gastropods.
In a messenger RNA molecule, untranslated regions (UTRs) are present at:
I. 5' end before start codon
II. 3' end after stop codon
III. 3' end before stop codon
IV. 5' end after start codon