- What are macromolecules?
- Functions of macromolecules
- Structure of macromolecules
- Importance of macromolecules
- Natural macromolecules
- Synthetic macromolecules
We explain what macromolecules are, their functions and their types of structure. In addition, natural and synthetic macromolecules.
A macromolecule can be made up of hundreds of thousands of atoms.What are macromolecules?
Macromolecules are molecules of enormous size, that is, they are made up of thousands or hundreds of thousands of atoms. They can be biological in nature, the result of the processes that occur in living organisms, or synthetic, produced by the human being in chemical or biological laboratories.
The term macromolecules was coined in 1920 by Hermann Staudinger, Nobel Laureate in Chemistry. Back then he referred to macromolecules as molecules they weighed more than 10,000 daltons of atomic mass, although they can weigh much more.
Macromolecules that are made up of units of smaller molecules (called monomers) that repeat themselves making up their entire structure are called polymers. Polymers can also be natural or synthetic, for example, protein, the nucleic acids and carbohydrates are natural polymers, while carbohydrates plastics and synthetic fibers are synthetic polymers.
It is important to understand the difference between macromolecule and polymer, because although they are both large, they are not exactly the same. There are macromolecules that are not polymers, because they are not made up of a repeating molecular unit (monomer), although they are still large. For example, fats and macrocycles are macromolecules, but they are not polymers. On the other hand, there are some medium polymers, that is, their size is not as large as that of a macromolecule.
Functions of macromolecules
Macromolecules can have very different functions, depending on which one we are talking about. For example, glucose macromolecules are an energy source for living organisms.
A very different example is the DNA macromolecule, which is basically a cellular memory device used to synthesize proteins or to replicate cells.
On the other hand, proteins fulfill structural and transport functions and can also act as catalysts.
Synthetic macromolecules, such as polyethylene and nylon polymers, are widely used in chemical industry to make plastics or as insulators.
Structure of macromolecules
Macromolecules, in general, are composed of smaller molecular units that are linked by covalent bonds, by hydrogen bonds, by Van der Waals forces or by hydrophobic interactions. In all cases, they compose large molecular structures that contain thousands of atoms arranged in fixed sequences, resulting in compounds of very high molecular weight.
In addition, depending on their structure, macromolecules can be:
- Linear When they form long chains that repeat some order of monomers, joined together by head and tail.
- Branched. When each monomer can join other chains, forming branches (like trees) of different sizes at a certain distance from the main chain.
On the other hand, macromolecules can be classified according to their composition in:
- Homopolymers. They are made up of a single type of monomer that repeats itself throughout its molecular structure.
- Copolymers. They are made up of more than one type of monomer.
Importance of macromolecules
Macromolecules are distinguished from other natural and synthetic molecules in that they have a huge volume and molecular weight. As a consequence, its properties are more complex and useful than those of other molecules. For example, man-made polymers allow the creation of novel materials with unforeseen applications.
On the other hand, certain biological macromolecules perform complex tasks, either as a contributor of material and / or of Energy for other processes, or as mechanisms of action biochemistry, as with insulin, the human body's sugar regulating hormone, made up of 51 amino acids.
Natural macromolecules
Natural macromolecules are usually compounds very specific that fulfill vital functions. In some cases they function as a metabolic input (such as carbohydrates) and in others they are structural molecules (such as carbohydrates). lipids).
They are also key players in extremely complicated processes, such as the DNA and the RNA, involved in cell replication or mitosis. Some simple examples of natural macromolecules are starch, cellulose, glycogen, fructose, glucose or lignin present in wood.
Synthetic macromolecules
Synthetic molecules are, as their name suggests, those artificially synthesized by the human being through various chemical processes in which the binding of monomers is controlled, enhanced or accelerated.
They are particularly important in the petrochemical industry and in the derivatives of the Petroleum, from which we obtain important organic materials polymeric type, like most plastics (polyethylene, PCV), synthetic fibers (polyester, nylon) or advanced materials technology (like carbon nanotubes).