Compounds in living organisms

A nutrient is a substance which is needed for growth, repair and metabolism. The three main nutrients are:

  • carbohydrates
  • proteins
  • lipids (fats and oils)

These nutrients are all examples of organic chemicals. This means that they all contain carbon atoms, covalently bonded to the atoms of other elements.

Carbon, CHydrogen, HOxygen, ONitrogen, N
Carbohydrate
Lipid
Protein

You can see from the table that these nutrients contain carbon, hydrogen and oxygen. Proteins also contain nitrogen, and sometimes sulfur.

Also, note that these nutrients contain hydrogen atoms, H, and not hydrogen gas, H2.