A carbohydrate is a biological molecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms.

In particular, we have one Hydroxyl groups (OH) attached to Carbons. These make carbohydrates Polar molecules, and Hydrophobic

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The term is most common in biochemistry, where it is a synonym of saccharide, a group that includes sugars, starch, and cellulose. The saccharides are divided into four chemical groups:

Classification

• Monosaccharide. Depending on the number of carbons, we call the sugar: diose, triose, tetrose, pentose, hexose, heptose, octose, etc.
  • Glucose (a cyclic sugar, very important one).
• Polysaccharides. Several monosaccharides joined together by Dehydration synthesis.
  • disaccharides. Two monosaccharides
  • Starch
  • Cellulose
  • Glycogen
• oligosaccharides,

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