Micromolecule Definition

Micromolecule, as the name suggest as are small molecules, having low molecular weight and are thus known as monomer. They play a vital role in various biological reactions. In a reaction, the fusion of monomers results in the formation of a macromolecule, also known as polymer.

Macromolecules have a high molecular weight and are formed when the micro molecule forms monomers. Thus, to form a macromolecule polymer, micro molecules forms monomers. For instance, protein is formed from amino acids which are monomers.

What is Micromolecule?

Various types of molecules are present in the cell, which provide the cell structure and carries out various biological functions. These molecules also fuse together to form a huge molecule known as macromolecule. Some of the macromolecules are lipids, proteins, nucleic acid and carbohydrates.

Glycerol, nucleotides, amino acids, fatty acid and monosaccharide are some of the vital micro molecules. Water and mineral are inorganic micro molecules which are very important. Micro molecules can form a macromolecule or exist in free form like water. In addition, reaction, micro molecules get inserted one after the other to form a macromolecule.

In condensation reaction, to form a macromolecule, combination of two micro molecule results in loss of water. Through various metabolic process, micro molecules are formed, which act as substrates. Thus, to stay healthy we need to eat diet which consist of both micro molecules and macromolecules. The amount of the content present within a particular food is mentioned on the packaging of the food.

Micromolecule Examples

Micro molecules are vital for life and are found within the body. Micro molecule example are amino acid, minerals, water, nucleic acid, fatty acid and sugar.

i. Minerals

Minerals are inorganic micro molecules, that regulate individual’s health. They are responsible for secreting enzymes and hormones. The smooth running of the bones, heart, muscles and brain is under control of minerals. There are some minerals which are required in larger amount like sodium, chloride, potassium, calcium and others.

However, there are minerals like cobalt, zinc, selenium, copper, iodine which are required in minute amount. These minerals could be obtained through the tablets or through the food we consume.

ii. Water

Water exist in a free form and is an inorganic molecule. Water comprises of two hydrogen atom and a single oxygen atom. Water is an extremely vital component, which is required by all types of living organism, and the body of such organism is majorly made from water. Water is being taken up either through foods which consist of water within them like vegetables and fruits or by drinking it.

Water has various functions like regulating body temperature, proper functioning of brain and elimination of waste, absorption of food, minimizes chances of constipation, disease, regulates blood circulation, cognitive functions, brightens up the mood, elevates energy level, keeps the bowel system clear and protects from getting dehydrated and improves the functioning of body. When we drink water, it results in generation of saliva, which functions as a lubricant and prevents friction and swelling of spinal cord, tissues and joints.

iii. Nucleic Acid

Nucleic acid are vital as they contain genetic information coded about each individual. The two macromolecule are DNA and RNA. Amino acid sequence is regulated by DNA, and these amino acids will further be coded to form proteins. Both of the macromolecule comprises of nucleobase, pentose sugar and a phosphate group. DNA are double stranded molecule, whereas RNA are single stranded.

iv. Fatty Acids

When the fat present within the body fuses, it forms fatty acids. Fatty acids regulate cholesterol level, blood pressure, absorbs vitamins like K, E, D, A, which are fat soluble, they are the energy source, protect the inner organs and membranes. Fats are of two types; saturated and unsaturated.

Unsaturated fats are healthy and are found in foods like avocado, almond, hazelnut, peanut butter, pumpkin seeds and etc. olive oil, sesame oil and peanut oil also contain unsaturated fatty acids. In packaged food, saturated fats are present like biscuits, dairy products, beef, pizza and etc. these type of food is unhealthy and is not good for health, thus should not be consumed in huge amounts.

Eating more of saturated food, will have an effect on the cholesterol level, result in becoming obese, increase the chances of cardiac arrest and heart conditions. Consumption of unsaturated food is healthy as it keeps the brain fit and reduces the chances of Alzheimer’s disease.

v. Amino Acids

There are 20 types of amino acids. From the amino acid, proteins are formed. Amino acid comprises of carbon chain, amino group and a hydroxyl group. The structure of amino acid is same but they vary in the carbon side chain, function, characteristics, weight and charge. There are two types of amino acid; essential and non-essential.

Essential amino acids are recruited from food, whereas non-essential amino acids are produced within the body. When various amino acid combine together it results in the formation of a protein, which ahs various functions like providing energy, maintaining Ph, body temperature, fluid level, movement of nutrients in the blood, helps the bones, behave as enzymes and hormones, storing and supporting the development and growth of an individual.

To form a protein the amino acids are connected to each other by peptide bond. The different type of protein are formed due to the various combination of amino acid. protein found in animal’s connective tissue is collagen, which forms the plumage, hair, horns, feathers and etc.

Example of storage proteins are in the seed; proteins are stored and in the egg albumin is present. Hemoglobin is a transporter protein, which provides oxygen to the body and takes carbon dioxide to the lungs. Insulin is a hormonal protein which maintains the sugar level in the body. Enzymes are also proteins, which catalyzes the reaction.

vi. Sugars

A sugar moiety comprises of hydrogen, carbon and oxygen. A micro molecule, which forms carbohydrate is glucose, which can exist in the linear form or in a cyclic form. When plants take up sunlight to produce chemical energy, glucose is formed, during photosynthesis, along with oxygen. The glucose formed is stored in the form of starch, that can be used by another organism.

Glucose is the easiest breakable molecule, which can be utilized by plants, animals and other organism. During respiration, glucose and oxygen provides carbon dioxide, water and liberates energy in the form of ATP, which is taken up by the cells. From a long chain of glucose, starch is produced.

Foods which comprises of starch are potato, which is an excellent energy source for living organism. In plants, glucose is stored in the form of starch and in animal, glucose is stored in the form of glycogen.

Myosin: Definition, Types, Structure, & Examples

Micromolecule Citations

Pound-wise but penny-foolish: How well do micromolecules fare in macromolecular refinement? Structure . 2003 Sep;11(9):1051-9.
The choice of anti-tumor strategies based on micromolecules or drug loading function of biomaterials. Cancer Lett . 2020 Sep 1;487:45-52.
Integrating Hormone- and Micromolecule-Mediated Signaling with Plasmodesmal Communication. Mol Plant . 2016 Jan 4;9(1):46-56.