Carbohydrates (sugar)

The most well known sugar is sucrose. That is the sugar people normally put in coffee or tea. The sucrose molecule (shown here) comprises one molecule of fructose and one of glucose (both monosaccharides).

Galactose is one of 3 sugars that are absorbed directly into the bloodstream (doesn't require any digestion)

Sugars have important functions, like storing energy (in the form of starch, in plants, or glycogen, in animals) and also as building blocks of more complex molecules like DNA.

Monosaccharides are the simplest form of sugar. They are the building blocks of all carbohydrates, like disaccharides (two monosaccharide units together) or polysaccharides (lots of units together forming a polymer) like starch or cellulose.

The general from of a sugar is C_x(H₂O)_y . Their formula indicates why the it is a carbohydrate: it is a combination of  C (carbon) with H₂O (water, hydro*) .

* check out word roots here

If the water is removed, black carbon is left. A typical dehydrating agent is sulfuric acid, which removes water from the carbohydrate molecules leaving carbon: