Biomolecules
Biomolecules, also known as biological molecules, are numerous substances which are produced by
cells and living organisms. They have various functions and structures. Biomolecules are essential for
living organisms and their daily activities. They are classified into four major categories, which are,
proteins, lipids, carbohydrates and nucleic acids. This essay will discuss all of these four biomolecules
and their functions and structure. What makes these biomolecules so special and suited for their
functions? (Khan Academy, 2019)
The structure & function of proteins
Proteins are the most multifunctional but complex molecules. Proteins are often described as the
building blocks of our bodies because they are included in all cells of the body. They are needed for
the maintenance and structure of our bodies’ organs and are an important component of the muscles.
All enzymes and non-steroid hormones are proteins. Some parts of our immune system also consist of
proteins. Some substances must also be bound to proteins in order to be transported in the blood. An
example of this is Hemoglobin that transports oxygen. (Khan Academy, 2019)
Proteins can be divided into different type of groups according to their functions: structural protein
(e.g collagen and elastin), storage protein (e.g casein, gluten and ovalbumin), muscle protein (actin
and myosin), functional protein (e.g enzymes, hormones), transport protein (haemoglobin,
myoglobin.) (Dr Mondal, 2018)
Proteins consist of amino acid chains, also known as Polypeptide chains. There are 20 different sorts
of amino acids. Which can be combined into an infinite number of protein patterns in short or long
chains. Nine of these twenty amino acids are essential to the body and needs to be absorbed through
our diets, these nine amino acids are Lysine, Leucine, Phenylalanine, Methionine, Threonine,
Tryptophan, Valine and last but not least Histidine. The other amino acids that our bodies need are
produced by the body itself. (Khan Academy, 2019)
The polypeptide chain that a protein contains is folded into a spheric three-dimensional shape. Its final
form is determined by the order of the amino acids. The natural state is when the protein is naturally
folded. The shape has a significance for the function of the protein.
The following points are the four levels of Photo credit: Khan Academy
structure for a protein: Image modified from OpenStax Biology modification of work
by the National Human Genome Research Institute.