Which structure has the least effect on tne ability of a virus to infect and replicate in a host cell

The ribosome structure has the least effect on the ability of a virus to infect and replicate in a host cell. That'd be the correct answer for your question.

Six amino acids have side chains that are polar but not charged. these are serine (ser), threonine (thr), cysteine (cys), asparagine (asn), glutamine (gln), and tyrosine (tyr). these amino acids are usually found at the surface of proteins, as discussed in the proteins 2 module.