Answer:
Carbon
Hydrogen
Oxygen
Nitrogen
Explanation:
The key elements of an amino acid are carbon (C), hydrogen (H), oxygen (O), and nitrogen (N), although other elements are found in the side chains of certain amino acids. However, carbohydrates do not contain the element Nitrogen and all carbohydrates, including sugar, therefore contain the same three elements: carbon, hydrogen and oxygen. Different arrangements of these elements form single units to make different types of carbohydrates.
