Unlike carbohydrates , proteins and nucleic acids they aren’t polymers but small molecules, with a molecular weights that range between 100 and 5000, and also vary considerably in polarity, including hydrophobic molecules, like triglycerides or sterol esters, and others more water-soluble like phospholipids or very short-chain fatty acids , the latter completely miscible with water and insoluble in non polar solvents.
The little or absent water-solubility of many of them means that they are subject to special treatments at all stages of their utilization, that is in the course of digestion , absorption , transport, storage and use.
While there is variation among the types of biological polymers found in different organisms, the chemical mechanisms for assembling and disassembling them are largely the same across organisms. Monomers are generally linked together through a process called dehydration synthesis, while polymers are disassembled through a process called hydrolysis. Both of these chemical reactions involve water. In dehydration synthesis, bonds are formed linking monomers together while losing water molecules. In hydrolysis, water interacts with a polymer causing bonds that link monomers to each other to be broken.