Topic 1 Internal Membranes and Enzymes

• What do membrane-bound organelles allow for?

  Compartmentalisation which enables complex and multiple metabolic reactions to occur at the same time
• What are enzymes?

  Proteins that acts as biological catalysts. They are specific and are either intracellular or extracellular
• What do biochemical pathways ensure?

  The product on one step becomes the reactant of the next step
• What is the active site on an enzyme?

  Is where the substrate molecules attach to the enzyme's surface. Enzymes can denature if the active site changes.
• What is the lock-and-key model?

  The shape of the substrate molecule is an exact fit to the enzyme's active site
• What is the induced fit model?

  Enzymes active site is not fixed, modifying its shape to ensure the substrate fits
• What are the benefits of enzymes?

  Reduce activation energy, not destroyed or altered by reactions, can word in either direction
• How does a higher temperature impact enzyme reactions?

  Increase reaction as enzyme and substrate collide more often. If temp is too high, the enzyme can denature.
• How does pH level impact enzyme action?

  They are pH sensitive, and can be denatured or shape of substrate changes
• How does the enzyme concentration impact reactions?

  Rate of reaction are proportional to the amounts of substrate present
• How do non-competitive inhibitors impact enzyme action?

  Don't bind to the active site, but change active site shape
• How do competitive inhibitors impact enzyme action?

  Bind to active site
• What are cofactors and coenzymes do?

  substances that activate an enzyme