The sharing of electrons in alcohol as an example, are much more losely bound; this is a common way that organic compounds are formed, and why organic reactions can proceed at lower temperatures, mediated by enzymes. No enzyme could break down NaCl alone to make pure sodium metal and chlorine gas.
Protein can be categorized into two types: complete and incomplete proteins. Proteins are made up of smaller units, called amino acids. Complete proteins contain all of the amino acids your body needs and include meat, fish, poultry, dairy, and soy products.
There are two basic types of transmembrane proteins: alpha-helical and beta-barrels. Alpha-helical proteins are present in the inner membranes of bacterial cells or the plasma membrane of eukaryotes, and sometimes in the outer membranes. This is the major category of transmembrane proteins. In humans, 27% of all proteins have been estimated to be alpha-helical membrane proteins.