1. Proteins, The Molecules That Are Essential For Life
Proteins are large molecules that are essential for life because they are the only source of nitrogen in the body. They are made of amino acids, which are small molecules made of carbon, hydrogen, oxygen and nitrogen. There are about twenty in total. These combine in multiple ways to form proteins of different sizes and complexity. It is thought that about 100 amino acids are required to form a protein.
There are so many possible combinations of amino acids that we still do not know of all the different proteins that exist. Some form the framework of every organ in the body (structural proteins), while others are functional such as those that constitute our antibodies, our enzymes, our hormones or our haemoglobin. The body also has the ability to convert one amino acid into another to suit its needs except for 8 of them, called essential amino acids. If one of them is missing or lacking in number, the process of protein synthesis is blocked.
It is also worth bearing in mind that all the cells of our body are made of proteins and that their organisation is genetically coded so that they are completely different in each individual. This is why organ transplants are sometimes rejected.
Finally, there are the following two types of protein: animal-based protein and plant-based protein, both of which are as important as each other.