Biological molecules - protein

• What are proteins primarily made of?

  Amino acids
• What are the monomers that make up proteins?

  • Amino acids
• What is a polypeptide?


  A polypeptide is formed when more than two amino acids join together
• Which chemical elements are found in all amino acids?


  Carbon, oxygen, hydrogen, and nitrogen
• What type of bond joins amino acids together?

  Peptide bonds
• What is the reverse reaction of forming a dipeptide?


  It adds a molecule of water to break the peptide bond
• What are the four levels of protein structure?


  1. Primary structure
  2. Secondary structure
  3. Tertiary structure
  4. Quaternary structure
• What is the primary structure of a protein?


  The sequence of amino acids in a polypeptide chain joined by peptide bond
• What is the secondary structure of a protein?

  The folding or coiling of the polypeptide chain, coiled into an Alpha helix or folded into a beta pleated sheet
• What is the tertiary structure of a protein?


  The overall 3D shape of a single polypeptide chain
• What is the quaternary structure of a protein?


  The arrangement of multiple polypeptide chains in a protein
• What type of bonds are in the secondary structure of a protein?


  Hydrogen bonds
• what are the types of bonds found in the tertiary structure of a protein?


  Hydrogen

  Ionic

  Disulfide

  Hydrophobic and hydrophilic interactions
• what are ionic bonds?


  attractions between negatively charged R groups and positively charged R groups on different parts of the molecules.
• What are disulfide bonds?


  when 2 molecules of amino acid cysteine come close together, and the sulfur atom in one bonds with the sulfur atom in the other cysteine.
• What is the structure and function of globular proteins?

  Round and compact

  functional protein
• What are some functions of globular proteins in living organisms?

  • Haemoglobin(conjugated protein): carries oxygen in red blood cells
  • Insulin: regulates blood glucose levels
  • Amylase: catalyzes starch breakdown in digestion
• What is the prosthetic group in haemoglobin?

  Haem
• What is the role of iron in the haem group of haemoglobin?

  Oxygen binds to iron
• What is the structure and function of fibrous proteins?

  insoluble and strong

  structural proteins
• What are three examples of fibrous proteins and their functions?


  • Collagen: found in connective tissues, provides strength
  • Keratin: found in external structures, provides toughness
  • Elastin: found in elastic tissues, allows stretching
• General structure of an amino acid

  Amino acid:

  A) Variable R group

  B) Carboxyl group

  C) Amine group

  D) H

  E) H

  F) N

  G) R

  H) H

  I) C

  J) C

  K) 0

  L) OH

  
• how are amino acids broken and made?

  broken - hydrolysis

  made - condensation