The peptide portion of any protein without its prosthetic group is called . The peptide portion of any protein without its prosthetic group is called .

Apoprotein

Explanation:

A peptide is a molecule formed as a result of the linking of amino acid molecules by a peptide bond. The peptide is the backbone of polypeptides and subsequently, protein molecules. Enzymes are proteinous molecules that serve as biological catalysts. The prosthetic group of a protein/enzyme is a metallic attachment to the protein, which plays roles that are vital to its functioning.

However, when the peptide portion of a protein molecule lack its prosthetic group, the protein is called an APOPROTEIN.

a. possible errors

d. new questions

explanation:

predictions and planning happen before. a summery comes after. errors you get after investigation and new questions propose what you can look for in the future.