Final answer:
Peripheral proteins are not embedded in the hydrophobic portion of the lipid bilayer; instead, they are associated with the membrane surface and do not penetrate the hydrophobic core.
Step-by-step explanation:
The types of proteins that are not embedded in the hydrophobic portion of the lipid bilayer at all are peripheral proteins. These proteins are more loosely associated with the membrane, as opposed to integral proteins and transmembrane proteins, which span the hydrophobic interior of the bilayer. Peripheral proteins are typically connected to the membrane surface either by interactions with the polar head groups of the lipids or by binding to integral proteins. They may serve various functions including enzymes, structural attachments, or as part of the cell's recognition sites but do not embed within the hydrophobic core of the lipid bilayer.