Biomolecules – Concept, types, functions and importance

We explain what biomolecules are and how organic and inorganic biomolecules are. What are its functions and importance.

Lipid - biomolecule
Lipids have a hydrophobic side, that is, they repel water.

What are biomolecules?

Biomolecules or biological molecules are all those molecules typical of living beings, either as a product of their biological functions or as a constituent of their bodies. They come in a huge and varied range of sizes, shapes, and functions. The main biomolecules are carbohydrates, proteins, lipids, amino acids, vitamins, and nucleic acids.

The body of living beings is made up mainly of complex combinations of six primordial elements: carbon (C), hydrogen (H), oxygen (O), nitrogen (N), phosphorus (P) and sulfur ( S). This is because these elements allow:

  • The formation of extremely stable covalent bonds (which share electrons) (single, double or triple).
  • The formation of three-dimensional carbon skeletons.
  • The construction of multiple functional groups with extremely different and particular characteristics.

For this reason, biomolecules They are usually made up of this type of chemical elements. Biomolecules share a fundamental relationship between structure and functions, in which the environment in which they are found also intervenes. For example, lipids have a hydrophobic part, that is, they repel water, so they tend to organize in the presence of it in such a way that the hydrophilic ends (attracted by water) are in contact with the environment and the hydrophobes remain to your protection. These types of functions are essential for understanding the biochemical functioning of living organisms.

According to their chemical nature, biomolecules can be classified into organic and inorganic.

Inorganic biomolecules

Inorganic biomolecule
Inorganic biomolecules are not based on carbon.

Inorganic biomolecules are all those that are not carbon-based, except some like CO2(g) and in CO. Are they can be part of both living beings and inanimate objectsBut that does not mean they cease to be indispensable for the existence of life. These types of biomolecules do not form monomer chains as in the case of organic ones, that is, they do not form polymers, and can be made up of different chemical elements.

Some examples of inorganic biomolecules are water, certain gases such as oxygen (O2) or hydrogen (H2), NH3 and NaCl.

Organic biomolecules

Biomolecule - proteins
Organic biomolecules are the product of the body’s own chemical reactions.

Organic biomolecules are based on carbon chemistry. These biomolecules are the product of chemical reactions in the body or the metabolism of living beings. They are mainly made up of carbon (C), hydrogen (H) and oxygen (O). They can also have as part of their structure metallic elements such as iron (Fe), cobalt (Co) or nickel (Ni), in which case they would be called trace elements. Any protein, amino acid, lipid, carbohydrate, nucleic acid or vitamin is a good example of this type of biomolecules.

Functions of biomolecules

DNA - biomolecule
Heredity in living beings is possible thanks to the existence of DNA.

Biomolecules can have various functions, such as:

  • Structural functions. Proteins and lipids serve as supporting material for cells, maintaining the structure of membranes and tissues. Lipids also constitute the energy reserve in animals and plants.
  • Transport functions. Some biomolecules serve to mobilize nutrients and other substances throughout the body, inside and outside cells, binding to them through specific bonds that can then be broken. An example of this type of biomolecule is water.
  • Catalysis functions. Enzymes are biomolecules capable of catalyzing (accelerating) the speed of certain chemical reactions without being part of the reaction, therefore, they are neither a reactant nor a product. These types of biomolecules regulate a large group of chemical and biological processes that occur in the human body, animals and plants. There are also inhibitors, which are molecules that slow down certain chemical reactions and, therefore, also intervene in the regulation of chemical and biological processes. Examples of enzymes are amylase, which is produced in the mouth and allows you to break down starch molecules, and pepsin, which is produced in the stomach and allows you to break down proteins into amino acids.
  • Energy functions. The nutrition of living organisms can be autotrophic, when they are capable of synthesizing the fundamental compounds for their metabolism at the expense of inorganic molecules (without depending on another living being), or heterotrophic, when they obtain the organic matter necessary for their metabolism from organic matter synthesized by other autotrophic or heterotrophic organisms (depending on another living being). In both cases, the energy necessary to sustain life in living organisms is obtained through a process called oxidation, which consists of breaking down glucose to simpler forms for energy. Lipids are also an essential source of energy.
  • Genetic functions. DNA (deoxyribonucleic acid) is a nucleic acid that contains all the genetic information necessary for the development and functioning of all living things. In addition, he is responsible for transmitting hereditary information. On the other hand, RNA (ribonucleic) is a ribonucleic acid that is involved in the synthesis of proteins necessary for the development and functioning of cells. DNA and RNA do not act alone, DNA uses RNA to transmit genetic information during protein synthesis. These two biomolecules constitute the basis of the genome (all the genetic material that a particular organism contains), therefore, they determine what a specific species or individual is.

Importance of biomolecules

Biomolecules are essential for the birth, development and functioning of all cells that make up living organisms. They fulfill vital functions of support, regulation of processes and transport of substances in each of the cells that make up the tissues, organs and organ systems.

The lack of a certain biomolecule in a living organism can cause deficiencies and imbalances in its functioning, causing its deterioration or death.

Bioelements and biomolecules

Bioelements are called chemical elements from which biomolecules are composed, therefore, they are the elements present in living beings.

Bioelements can be classified as:

  • Primary bioelements. They make up 99% of the living matter of all known living things. They are: carbon (C), oxygen (O), hydrogen (H), nitrogen (N), sulfur (S) and phosphorus (P).
  • Secondary bioelements. They are those that, although they are essential for life and for the proper performance of the body, are required in moderate amounts and for specific purposes. They are: sodium (Na), calcium (Ca), magnesium (Mg), potassium (K), chlorine (Cl) and fluorine (F).

In addition, there are trace elements that are necessary for life, but in very low quantities (0.1% of the bioelements in the body). Some examples are: iron (Fe), iodine (I), chromium (Cr), copper (Cu), Zinc (Zn) and Boron (B).