Carbohydrates – Definition, Classification, Sources, Importance

Carbohydrates – A biomolecule, sometimes known as a biological molecule, is a word that refers to molecules found in living things that are required for one or more biological processes, such as cell division, morphogenesis, or development. Large macromolecules (or polyanions) like proteins, carbohydrates, lipids, and nucleic acids, as well as tiny molecules like primary metabolites, secondary metabolites, and natural products, are all examples of biomolecules.

Biomolecules are essential components of living creatures. While endogenous biomolecules are created within the organism, organisms often require external biomolecules, such as specific nutrients, to exist.

In this article, we will learn in detail about carbohydrates, its classification, sources, and its importance.

What are Carbohydrates?

In a human body the cells are depended on on the glucose for fuel. Carbohydrates plays an important role in providing the glucose to the cells in human body so that it can function properly. Carbon, hydrogen, and oxygen are the three components that make up carbohydrate biomolecules. (CH₂O)_n is the typical empirical formula for carbohydrates. They are one of the vital dietary nutrients since they provide our bodies with quick energy.

Check: Glucose Chemical Formula

Classification of Carbohydrates

Based on their structures, carbohydrates are divided into monosaccharides, disaccharides, oligosaccharides, and polysaccharides.

• Monosaccharides –Simple sugars with a free ketone or aldehyde group are known as monosaccharides. They can’t be hydrolyzed anymore because they’re the simplest of sugars. C_nH_2nO_n or C_n (H₂O) _n is their chemical formula. Depending on their ketone or aldehyde group, monosaccharides are categorised as tiroses, tertroses, pentoses, and so on, as well as ketoses or aldoses. Glucose, fructose, galactose, glycerose, ribose, and ribulose are among examples.

Structure of Glucose

Structure of Fructose

• Disaccharides – Disaccharides hydrolyze into two molecules of the same or distinct monosaccharides. The oxide bond, which is generated by the loss of a water molecule, connects the two monosaccharide units, and this linkage is known as glycosidic linkage. Sucrose is a typical disaccharide that breaks down into glucose and fructose when hydrolyzed. The other two main disaccharides are maltose and lactose (commonly known as milk sugar). There are two α-D-glucose in maltose and two β-D-glucose in lactose that are joined by an oxide bond.

• Oligosaccharides – When sugars are hydrolyzed, they break down into two to ten molecules of monosaccharides. A disaccharide is an oligosaccharide that breaks down into two monosaccharide molecules upon hydrolysis, whereas trisaccharides, tetrasaccharides, and so on are oligosaccharides that break down into three or four monosaccharide molecules. Disaccharides have the chemical formula C_n (H₂O)_n-1, whereas trisaccharides and others have the chemical formula C_n (H₂O)_n-2, and so on. Sucrose, maltose, lactose, raffinose, and stachyose are examples of oligosaccharides.
• Polysaccharides – Long monosaccharide molecules are linked together by a glycosidic linkage to form polysaccharides. The majority of them, such as Starch, serve as food storage. Plants use starch as their primary storage polysaccharide. It is a glucose polymer made up of two components: Amylose and Amylopectin. Cellulose is one of the most common polysaccharides found in plants. It is made up of β-D-glucose units linked together by a glycosidic bond between C₁ of one glucose unit and C₄ of the next.

• Starch- Starch is a carbohydrate that plants store as an energy source. Amylose and amylopectin are two forms of polymeric chains found in them. Amylopectin has a branching structure with α1–4 and α1–6 glycosidic linkages, whereas amylose has a linear structure with α1–4 glycosidic links.

Functions of Carbohydrates

• Carbohydrates are the major or principal energy sources in our bodies.
• They have a role in fat metabolism as well.
• Carbohydrates keep you out of ketosis.
• This is a kind of connective tissue.
• Carbohydrates keep the body’s digestive system running smoothly.
• Carbohydrate fibers can help reduce blood cholesterol levels.
• Because carbohydrates prevent protein from being burnt, they are needed to construct and repair.
• Carbohydrates provide the central nervous system with energy.
• They come in a variety of forms, including sugar, glucose, starch, and fiber.

Sources of Carbohydrates

• Many fruits contain simple sugars in the form of fructose.
• All dairy products include galactose.
• Lactose may be found in large quantities in milk and other dairy products.
• Maltose may be found in a variety of foods, including cereal, beer, potatoes, processed cheese, and pasta.
• Sucrose is derived from sugar and honey, both of which include trace quantities of vitamins and minerals.

Carbohydrate Foods

Nutrients are the compounds found in food that supply us with energy for development and repair. Carbohydrates may be found in both healthy and unhealthy food. They can be found in a variety of forms, including sugars, starch, and fibres.

Carbohydrates in healthy food consist of both animal and plant sources which include:

• Corn
• Potatoes
• Milk Products
• Fresh Fruits
• Vegetables

Carbohydrates in Unhealthy food includes:

• White Bread
• Artificial Sugar
• Pastries
• Soda
• Other Highly Processed Foods

Importance of Carbohydrates

1. Carbohydrates aid in metabolism and provide our bodies with energy in the form of glucose.
2. Plant cells are made up of the disaccharide cellulose. Plant cellulose is also utilised in the production of papers, textiles, and wood for building.
3. Photosynthesis, which manages the oxygen and carbon dioxide gas balance among plants and animals, is one of the most important processes in our biosphere. Plants utilise sunlight and carbon dioxide to release oxygen into the atmosphere, while glucose is generated and stored as a type of energy in plants. When animals eat plants, they acquire energy from the stored carbohydrate, and we may survive as a result.
4. Carbohydrates play an important role in our diet since they are one of our body’s main sources of energy.
5. Plants store starch, which includes thousands of glucose units, as an energy source.
6. Glycogen is a complex carbohydrate stored in animal cells that breaks down into simple glucose molecules during stress and muscle exercise.
7. Arthropods’ exoskeletons are composed of chitin, a complex carbohydrate.

Importance of Carbohydrates in Human Body

Our brain, heart, kidneys, and central nervous system all run on carbohydrates. Carbohydrates, along with lipids and proteins, are an important part of our diet. Our bodies convert carbs in meals to glucose, which gives us energy.

When the body eats too many carbs, it stores them in the liver cells as glycogen, a complex carbohydrate. Despite the fact that glucose is essential for delivering energy to our bodies, our blood sugar levels must be controlled in order to avoid significant health problems such as diabetes. Insulin is a hormone produced by the pancreas that lowers blood sugar levels and stores them as fat in the liver and muscles.

Importance of Carbohydrates in all Living Organisms

• Carbohydrates are necessary for all living things in our environment to survive. They are all organisms major sources of energy.
• Sugar molecules such as ribose and deoxyribose make up the majority of genetic materials (DNA and RNA) in living organisms. The polymer’s backbone is a sugar-phosphate-sugar chain, which forms a helical shape.
• ATP (Adenosine Triphosphate), the most important energy-transfer molecule in living beings, is also made from ribose sugar, a carbohydrate.
• Green plants convert carbon dioxide into organic substances such as sugars, which supply energy to the plants.
• In the soil, certain carbohydrates enhance seed germination and root elongation.
• Some rare sugars are employed in the pharmaceutical sector to make blood sugar-controlling medications.
• Anti-inflammatory properties of some complex oligosaccharides and oligonucleotides aid in the treatment of cancer.
• Antiviral medicines containing nucleoside analogues of uncommon sugars are used to treat HIV and HCV.

Importance of Carbohydrates in Our Diet

Carbohydrates are a rich source of vitamins, minerals, and nutrients, as well as providing energy to our bodies. They give immediate energy in the form of glucose, which is our body’s major source of energy and may be stored. These carbs should be included in our diet in the form of bread, potatoes, fibers, fruits, vegetables, and whole grains.

Importance of Carbohydrates for Athletes

• Energy- Carbohydrates are broken down into glucose molecules, which are stored in the liver and muscles and utilised later while exercising. Carbohydrates provide the majority of the energy that our minds and bodies require to perform correctly. Fatigue is postponed as a result of the existence of a sufficient quantity of carbohydrates in the body, which increases athletic performance.
• Increase in Muscle Mass- To grow muscle, a sufficient amount of protein is essential. When the body’s glucose consumption is high yet there isn’t enough stored, the body begins to break down proteins to fulfil its energy needs.
• Protein can aid in the free repair and rebuilding of muscle tissue if enough carbs are supplied to muscles, which maximises muscular development. A balanced diet rich in carbs such as grains, wheat, yoghurt, milk, fruits, vegetables, juices, and other fruits and vegetables is essential for athletes to maintain their performance and muscular potential.

Carbohydrates- FAQs

What is the importance of carbohydrates in nutrition?

Carbohydrates are essential for good nutrition since they provide energy to our bodies. Vitamins, minerals, and nutrients are abundant in them. They give immediate energy in the form of glucose, which is a major energy source that may be stored. These carbs should be included in our diet in the form of bread, potatoes, fibres, fruits, vegetables, and whole grains.

What is the importance of carbohydrates in living organisms?

Carbohydrates are necessary for all living things in our environment to survive. They are all organisms’ major source of energy. They aid in the production of genetic materials, as well as plant and animal cell architecture. Green plants make them and utilise them as energy in the form of ATP.

What is the importance of carbohydrates in energy consumption?

Carbohydrates are our bodies’ most efficient energy source. Our brain, heart, and other critical organs of our body get this energy, which gives them potential.

What is the function of carbohydrates?

Carbohydrates serve a variety of purposes in the body, including storing energy, providing energy for important tasks, regulating blood sugar, and supplementing fats and proteins for other purposes.

What is starch?

Starch is a kind of carbohydrate that plants use to store energy. It contains two types of polymeric chains: amylose and amylopectin. Amylopectin has a branching structure with glycosidic connections α1–4 and α1–6, whereas amylose has a linear structure with α1–4 glycosidic linkages.

What is monosaccharide?

It is a kind of carbohydrate with only one sugar molecule in it. Hydrolysis cannot break them down into smaller sugar molecules. Glucose, fructose, and galactose are examples of monosaccharides.