It has been estimated that about 18% of the human body is made up of protein. Like carbohydrates and fats, proteins are made up of the elements carbon (C), hydrogen (H) and oxygen (O) but they also contain nitrogen (N).
Download the Word file (see link below) to read this teacher resource, which provides information about proteins, specifically amino acids, peptide bond, peptides and proteins and types of proteins. It follows on from the article about macronutrients, giving more detail about this important group of energy-rich food substances.
