Carbohydrates and proteins are two types of macromolecules. Furthermore, they are organic compounds composed of carbon, hydrogen and oxygen atoms. In addition, proteins contain nitrogen, sulfur and phosphorus. Both types of macromolecules are important organic compounds, and they perform many different functions within the living organisms. However, they differ structurally and functionally. Monosaccharides are the building blocks of carbohydrates while amino acids are the building blocks of proteins.
1. Overview and Key Difference
2. What are Carbohydrates
3. What are Proteins
4. Similarities Between Carbohydrates and Proteins
5. Side by Side Comparison – Carbohydrates vs Proteins in Tabular Form
What are Carbohydrates?
Carbohydrates are the most abundant organic molecules in nature that constitute C, H and O. Also it is one of the key energy sources in living organisms. Besides, they are macromolecules composed of monomers called monosaccharides. Monosaccharides are simple sugars such as glucose, fructose and galactose, etc. Two monomers link together and form disaccharides such as sucrose, maltose, etc. Furthermore, carbohydrates exist as oligosaccharides and polysaccharides. Oligosaccharides contain three to six monomers while polysaccharides contain many monosaccharides.
Accordingly, energy production is mainly carried out using carbohydrates, especially by glucose since carbohydrates are available for immediate energy requirements. In animal tissues, carbohydrates can be seen in the form of glycogen while in plants, carbohydrates are found as starch. Furthermore, carbohydrates are water-soluble biomolecules, and they can release 4 kcal per one gram. Fruits, vegetables and grains are rich in carbohydrates. Starch and sugar are the most abundant and important elements in the human diet. Moreover, carbohydrates are not only energy sources, but they also play a structural role in the living organisms.
What are Proteins?
Proteins are organic compounds made up of interlinked chains of amino acids, which consist of carbon, hydrogen, oxygen, nitrogen, and sulfur. Amino acids are two types namely essential and non-essential amino acids. In the human digestive tract, proteins break down into its monomers; amino acids by enzymes and then the amino acids easily travel into the bloodstream. In facts, proteins are essential for the growth and maintenance of the human body. They are also used in conjunction with other molecules to form cellular membrane particles, nucleic acids, vitamins, enzymes, and hormones, etc. In addition, the proteins are a requirement in the formation of the red cells and blood in general.
Likewise, proteins act as a source of energy, and in exercises as the building component of muscles, it is imperative to maintain good health with exercise. Similar to carbohydrates, proteins contain energy and one gram of protein releases 4 kcal of energy. Furthermore, proteins are not only energy containing macromolecules, but also proteins fulfil many other functions in the living organisms. Enzymes are proteins. They are the catalysts of all biochemical reactions. Some hormones are also proteins. They regulate most of the bodily functions. Furthermore, some neurotransmitters are proteins. They are important in signal transmission. Besides, many proteins are structural proteins such as keratin, collagen, etc.
What are the Similarities Between Carbohydrates and Proteins?
- Carbohydrates and Proteins are important macromolecules.
- They contain C, H and O.
- Furthermore, they are energy sources.
- Both carbohydrates and proteins are essential organic compounds.
- They have similar molecular makeup.
- Both carbohydrates and proteins give out the energy of 4 kcal per gram.
What is the Difference Between Carbohydrates and Proteins?
Both proteins and carbohydrates are components in our diet. Simple sugars such as glucose and fructose link with each other by glycosidic bonds and form carbohydrates. On the other hand, amino acids link with each other by peptide bonds and form proteins. Therefore, this is the key difference between carbohydrates and proteins. Furthermore, carbohydrates are the main energy source in our body while proteins are the building blocks of our body. Thus, it is another difference between carbohydrates and proteins.
Moreover, a further difference between carbohydrates and proteins is that enzymes such as amylase, sucrase and maltase catalyze the carbohydrate digestion within our GI tract while proteases and peptidases catalyze the protein digestion.
Below infographic presents more details on the difference between carbohydrates and proteins.
Summary – Carbohydrates vs Proteins
In summary of the difference between carbohydrates and proteins, carbohydrates are the main energy source of our body while proteins are the building blocks of our body. Both are important macromolecules composed of simple sugars and amino acids respectively. Carbon, hydrogen and oxygen are the main elements of carbohydrates and proteins. Other than C, H and O, proteins contain S and N. Furthermore, compared to carbohydrates, proteins are structurally more important. Besides, all enzymes, many hormones and many neurotransmitters are proteins. They are really important for a healthy person.
1. “Carbohydrate.” Wikipedia, Wikimedia Foundation, 3 Jan. 2019. Available here
2. Nordqvist, Christian. “Protein: Sources, Deficiency, and Requirements.” Medical News Today, MediLexicon International, 24 Aug. 2018. Available here