Proteins

Proteins

1. Proteins are made from long chains of amino acids.

   • They fold to make different shapes.
   • Proteins act as: Structural components of tissues, hormones, antibodies, enzymes

2. Enzymes are proteins and biological catalysts.

   • Smaller molecules fit into enzymes.
     • These molecules are called 'substrates'. They fit perfectly into the enzyme's active site.
     • If an enzyme changes shape, the active site will also change shape. This is called being denatured.
       • Enzymes can be denatured by high temperatures or change in pH.

3. There are different types of enzymes.

   • Amylase: Starch > sugars, produced by salivary gland, pancreas and small intestine.
   • Lipase: Lipids > fatty acids + glycerol, produced by pancreas and small intestine.
   • Protease: Proteins > amino acids, produced by stomach, pancreas and small intestine.

4. The stomach produces hydrochloric acid.