Biological Molecules

• What is the tertiary structure of a protein?

  Further coiling and folding of the chain
• What is the quaternary structure of a protein?

  Assembly of multiple polypeptide chains
• What are the functions of different proteins?

  1. Enzymes: catalyze metabolic reactions
  2. Antibodies: involved in immune response
  3. Transport proteins: move molecules across membranes
  4. Structural proteins: provide strength and support
• What is the Biuret test used for?

  To test for the presence of proteins
• What are the two stages of the Biuret test?

  1. Add sodium hydroxide to make the solution alkaline
  2. Add copper(II) sulfate solution
• What color indicates the presence of protein in the Biuret test?

  Purple
• What happens if no protein is present in the Biuret test?

  The solution stays blue
• What is an enzyme?

  A biological catalyst that speeds up reactions
• What is the role of enzymes in metabolism?

  They catalyze metabolic reactions
• What is the active site of an enzyme?

  The part where the substrate binds