Читать книгу Astrobiology - Charles S. Cockell - Страница 76

If we had to identify one feature of life that stands out when we are discussing the formation of molecules, we would probably say that it has a propensity to form chains. Perhaps this isn't surprising. Life is complex, and if we want to build complex molecules, we would intuitively suggest that the best way to do this is to take simple molecules and string them together into more complex chains. All the major classes of molecules in life result from this process of putting single molecules (monomers) together into chains (polymers) in the process of polymerization.

In this chapter, we look at the four major classes of molecules from which life is made and consider their basic characteristics. As we study these molecules, think about the features that are common between them, particularly in light of an astrobiologist's question of what is universal about them. In advance, you will notice that all of them are chains, and despite performing quite different functions, all of them are assembled by linking together monomers of different molecules.