Protein

Proteins are composed of:

1. Carbon
2. Hydrogen
3. Oxygen and
4. Nitrogen

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Protein

• Consists of repeating units of amino acids.
• There are 20 common amino acids.
• The bond between amino acids is called a peptide bond.
• A peptide is made of less than 20 amino acids.
• A polypeptide is made of 20+, protein is a long polypeptide chain.
• Amino acids link together in polypeptide chains to form proteins. An average protein is 500 amino acids long.
• Sources of protein include chicken, eggs and soya beans.

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Role of Proteins

1. Structural role: Keratin in hair and nails
2. Metabolic role:

• Enzymes
• Hormones