What are Carbohydrates?

Carbohydrates are molecules that consist of carbon, hydrogen, and oxygen atoms. Carbohydrates usually form in a ratio of 1 carbon atom to 2 hydrogen atoms to 1 oxygen atom. For example, glucose, a type of carbohydrate, has the chemical formula of C6H12O6. There are twice as many hydrogen atoms as carbon or oxygen atoms.


Classification of Carbohydrates

Carbohydrates are extremely diverse, and are classified into 4 broad categories: monosaccharides, disaccharides, oligosaccharides, and polysaccharides. Monosaccharides and disaccharides are sugars, while oligosaccharides and polysaccharides are not.


Monosaccharides are a type of sugar. They consist of 3-7 carbon atoms. Monosaccharides are the most common carbohydrates, and are most well-known.


Disaccharides are also a type of sugar. They consist of two monosaccharides joined together.


Oligosaccharides are not a type of sugar. They usually consist of 3-10 monosaccharides. These are the least common of all carbohydrates.


Polysaccharides are long chains of monosaccharides. They usually have 100’s of monosaccharides in their chains, and can even have 1000’s.


Importance of Carbohydrates

Our body gets carbohydrates from food. It breaks down carbohydrates to be used as energy. This energy can be made quickly, but does not last long. This is why your body needs to consume food often.

Food has lots of polysaccharides in it. Those polysaccharides end up in the stomach, and are broken down there into smaller carbohydrates; especially glucose. Glucose is pumped into the blood and is used as energy. It is stored in a polysaccharide called glycogen. The body then takes the energy from glycogen when needed.


Dehydration Synthesis and Hydrolyses

Dehydration synthesis is a process where two monosaccharides are combined. During this process, a water molecule is released as a bi-product. For example glucose and fructose both have a chemical formula of C6H12O6(they are arranged in different ways, which is why they are different molecules). When they join together, they create table sugar: C12H22O11. If the water molecule was not lost, the chemical formula would be C12H24O12. Since a water molecule is released, the formula would be C12H24O11-H2o, which is C12H22O11.

Hydrolyses is the opposite process of dehydration synthesis. A complex carbohydrate is broken down into different monosacchrides when a water molecule is added. Using the last example, C12H22O11 can be broken down into glucose and fructose when a water molecule is added.