Final answer:
Proteins can be linked to the cell membrane via a fatty acid. Integral proteins span the membrane and interact with fatty acids, while peripheral proteins attach to the membrane surface.
Step-by-step explanation:
Some proteins can be attached or anchored to the cell membrane by being linked to a fatty acid. This linkage helps to anchor the protein within the cell membrane's hydrophobic interior. Membrane proteins can be classified into two major categories: integral proteins and peripheral proteins. Integral proteins often span the entire membrane with hydrophobic domains interacting with the fatty acids, while peripheral proteins are more loosely associated and may interact with the polar head groups of phospholipids or integral proteins. The polar and charged amino acids on the surface of a membrane protein interact with the aqueous environment, while non-polar amino acids tend to be found within the hydrophobic interior of the membrane.