AMINO ACIDS Amino acids are the monomers from which proteins are made. The general structure of an amino acid as: where NH2 represents an amine group, COOH represents a carboxyl group and R represents a carbon-containing side chain. The twenty amino acids that are common in all organisms differ only in their side group.

Amino acids   During the clip, try and name some of the Amino acids they mention – competition for the most got!  Amino acids are the monomers that make up proteins. All Proteins (also called polypeptides) are made up from the 20 different amino acids. Outcomes: -Name the monomers that polymerise to form proteins -Describe the chemical groups of an amino acid -Name and draw some different amino acids with the R groups. -Explain how peptide bonds are formed and broken between amino acids to form/break dipeptides. -Use structural formula to show condensation and hydrolysis reactions of amino acids.

Amino acid structure  All amino acids have this structure.  The R group (side chain) differs for each amino acid.  Task: Draw this and find the side groups of 3 amino acids and draw and label these too. Outcomes: -Name the monomers that polymerise to form proteins -Describe the chemical groups of an amino acid -Name and draw some different amino acids with the R groups. -Explain how peptide bonds are formed and broken between amino acids to form/break dipeptides. -Use structural formula to show condensation and hydrolysis reactions of amino acids.

There are 20 amino acids, how many proteins are there?  Proteins (polypeptides) are made of large amounts of amino acids joined up together in a specific order.  Because of this you can make millions of different proteins just using the 20 different amino acids.  Task: How many polypeptides can you make from just 3 amino acids. Outcomes: -Name the monomers that polymerise to form proteins -Describe the chemical groups of an amino acid -Name and draw some different amino acids with the R groups. -Explain how peptide bonds are formed and broken between amino acids to form/break dipeptides. -Use structural formula to show condensation and hydrolysis reactions of amino acids.

Alanine Glycine Leucine Alanine Glycine Leucine

Forming Dipeptides – joining amino acids  Forming polypeptides (making proteins):  Breaking down polypeptides (making amino acids): Outcomes: -Name the monomers that polymerise to form proteins -Describe the chemical groups of an amino acid -Name and draw some different amino acids with the R groups. -Explain how peptide bonds are formed and broken between amino acids to form/break dipeptides. -Use structural formula to show condensation and hydrolysis reactions of amino acids.

The Peptide bond Q: What was the bond between two monosaccharides called? Q: What do you think the bond between two amino acids will be called? Outcomes: -Name the monomers that polymerise to form proteins -Describe the chemical groups of an amino acid -Name and draw some different amino acids with the R groups. -Explain how peptide bonds are formed and broken between amino acids to form/break dipeptides. -Use structural formula to show condensation and hydrolysis reactions of amino acids.

HW: Testing for Amino Acids  Research how to identify amino acids/separate a solution of amino acids using Thin Layer Chromatography paper.  In your Lab books: Title: Testing for Amino acids in an unknown solution.  Write an aim, equipment list, method and risk assessment.  Next lesson we are going to do this! Outcomes: -Name the monomers that polymerise to form proteins -Describe the chemical groups of an amino acid -Name and draw some different amino acids with the R groups. -Explain how peptide bonds are formed and broken between amino acids to form/break dipeptides. -Use structural formula to show condensation and hydrolysis reactions of amino acids.