Pictorial description of the 2D shapes of a fiber cross-section in polysaccharide and composite oligopeptide-polysaccharide networks. The addition of chondroitin D to CA (chitosan + alginate, red) leads to much bigger and thicker fiber CAD (CA + chondroitin, green); while the addition of the peptides P (KWK + EWE, purple) to the above polysaccharide networks with the formation of CAP (CA + P, black) or CADP (CAD + P, blue) completely disrupts the structures of polysaccharides and results in the fibers with the cross-section very similar to the pure peptide network P.