Essential Idea:  Proteins have a very wide range of functions in living organisms.
At SHS, Topic 2.4 is taught in the following class unit(s):​​
2.4.U1  Amino Acids are linked together by condensation to form polypeptides.
  • Describe polypeptide chain formation in terms of the formation of peptide bonds and condensation reactions.
  • Determine the number of peptide bonds given the number of amino acids in a polypeptide.
  • Define dipeptide, oligopeptides and polypeptide.  
2.4.U2  There are 20 different amino acids in polypeptides synthesized on ribosomes.
  • State the number of amino acids used by living organisms to make polypeptides.
  • Given an image of an amino acid, classify the amino acid chemical properties based on R group properties. 
  • Outline the role vitamin C plays in the conversion of proline to hydroxyproline.  ​
2.4.U3  Amino Acids can be linked together in any sequence giving a huge range of possible polypeptides.
  • Calculate the possible number of amino acid sequences given n number of amino acids.
2.4.U4  The amino acid sequence of polypeptides is coded for by genes.
  • Outline the relationship between genes and polypeptides.
2.4.U5  A protein may consist of a single polypeptide or more than one polypeptide linked together.
  • Outline the structure and function of three example proteins composed of two or more polypeptides linked together.
2.4.U6  The amino acid sequence determines the three-dimensional conformation of a protein.
  • Contrast the structure of globular proteins with the structure of fibrous proteins.
  • Describe the structure of membrane bound globular proteins.
2.4.U7  Living organisms synthesize many different proteins with a wide range of functions.
  • Contrast the generalized function of globular proteins with generalized function of fibrous proteins.
  • List ten functions of proteins in a cell or organism.
  • Describe the function of enzyme proteins.
  • Describe the function of hormone proteins.
  • Describe the function of immunoglobulin proteins.
  • Describe the function of pigment proteins.
  • Describe the function of structural proteins
2.4.U8  Every individual has a unique proteome.
  • Define proteome.
  • Contrast proteome with genome.
2.4.A1  Rubisco, insulin immunoglobulins, rhodopsin, collagen and spider silk as examples of the range of protein functions.
  • State the function of each of the following proteins:  rubisco, insulin, immunoglobulin, rhodopsin. collagen, spider silk, actin, myosin, casein, hemoglobin, acetylcholine receptor, oxytocin, prolactin, ferritin, billirubin, fibrinogen, transferrin and albumin.
2.4.A2  Denaturation of proteins by heat or by deviation of pH from the optimum.
  • Define denaturation.
  • Outline the effect of heat and pH on protein structure.
2.4.S1   Drawing molecular diagrams to show the formation of a peptide bond.
  • Draw peptide bond formation in a condensation reactions.
2.4.NOS  Looking for patterns, trends, and discrepancies- most but not all organisms assemble proteins from the same amino acids.
  • Explain the trend of organisms assembly of polypeptides from the same amino acids.
  • Describe a discrepancy of the trend of all organisms using the same amino acids to assemble polypeptides.

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