#29 Main nutrients: carbohydrates, fats and proteins
- taking in of nutrients which are organic substances and mineral ions, containing raw materials or energy for growth and tissue repair,
- assimilating them.
Large carbohydrate molecules such as starch, glycogen and cellulose are made up of long chains of smaller units - monosaccharides such as glucose - held together by chemical bonds.
Fats are made up of 3 units of fatty acids chemically bonded to 1 glycerol unit.
Proteins are made of long chains of amino acids chemically bonded together. There are about 20 different amino acids, their pattern in the chain can be quite complex and the molecules can be very large.