What is the relationship between lipids and proteins?

Lipids and proteins are two distinct types of biomolecules in biological systems. Lipids are a diverse group of hydrophobic organic molecules that serve various functions in energy storage, membrane structure, and signaling in biological systems. Proteins are large, complex macromolecules composed of amino acids that perform a wide range of functions, including structural support, transport, signaling, and regulation of biological processes in living organisms. While lipids and proteins have distinct structures and functions, there are several important relationships and interactions between lipids and proteins in biological processes. 

• Lipids play a key role in regulating the folding, organization, and final structure of all membrane proteins. 
• Lipids also have a direct impact on the function of membrane proteins and several amphitropic proteins that interact with the membrane surface reversibly. 
• Lipids and proteins are both integral components of cell membranes. Lipids form the membrane bilayer that acts as a barrier, separating the inside of the cell from its external environment. Embedded within this lipid bilayer are proteins that serve as channels controlling the movement of molecules in and out of the cell. The embedded proteins also serve as receptors that allow cells to communicate with their surroundings.  
• Lipoproteins, which are complexes made up of lipids and proteins, are involved in the transport of lipids in the bloodstream. 
• Apolipoproteins, which are a type of protein, play a key role in the transport and delivery of lipids in the bloodstream.