Claim: In helical, the protomers (structural unit of a protein) are not grouped in capsomeres but are bound to each other forming a ribbon-like structure which folds into a helix.
Evidence: 2) Helical- The protomers are not grouped in capsomeres, but are bound to each other so as to form a ribbon-like structure. This structure folds into a helix because the protomers are thicker at one end than at the other. In structural biology, a protomer is the structural unit of an oligomeric protein.