John F. Kennedy International Airport is one of the busiest airports in the New York City area, The Statue of Liberty, located on Liberty Island, is one of the cities biggest attractions.
There is a major difference between formal and functional regions. Formal regions are huge areas that are characterized by many activities. A functional region is a region that serves other regions, like major cities serving rural areas.
Functional distinctions may also be made between peptides and proteins. Peptides, however, may be subdivided into oligopeptides, which have few amino acids (e.g., 2 to 20), and polypeptides, which have many amino acids. Proteins are formed from one or more polypeptides joined together. Hence, proteins essentially are very large peptides.