protiens

• what are proteins made up of?

  one or more polypeptides
• what are proteins polymers of?

  monomers called amino acids
• what atoms do all proteins contain?

  C , H , O + N (some contain S)
• proteins: over 10 million different proteins in nature
• how many different amino acids?

  20
• all amino acids have the same basic structure
• Amino acid- name the groups

  A) amino group

  B) variable group

  C) carboxyl group

  
• what 2 ways do amino acid R groups vary?

  • chemical properties
  • size

  -->determines the structure and function of a protein
• label the amino acids

  A) peptide bond

  B) water

  C) dipeptide

  
• primary structure of a protein? (shape and bond)

  shape: sequence of amino acids in polypeptide chains

  bonds: peptide bonds, condensation oh NH2 and COOH

  -determined by dna base sequence in genes, produced by ribosomes (mRNA translation)
• secondary structure of a protein? (shape and bond)

  shape: alpha helix and beta sheet pleating of polypeptide chain

  bonds: caused by hydrogen bonding between peptide bonds of different amino acids in the polypeptide chain

  -forms spontaneously, hydrogen bonds are weak individually (easily broken by temperature and pH) BUT are strong collectively.
• tertiary structure of a protein? (shape and bond)

  shape: overall 3D structure of a polypeptide

  bonds: held together by 4 types of bond between r groups of amino acid within the polypeptide chain

  -hydrogen bonds , ionic bonds , disulfide bridges
• quaternary structure of a protein? (shape and bond)

  shape: overall structure of a protein which consists of more than one polypeptide chain

  bonds: intermolecular and intramolecular forces between the different polypeptide chains

  -mostly eukaryotic cells -> rough ER , 70s Ribosomes