Enzymes

• What is the primary function of enzymes in biological systems?

  Enzymes control cell reactions.
• How do enzymes affect the speed of reactions?

  They speed up the reactions.
• What is a characteristic of enzymes regarding specificity?

  Enzymes are very specific.
• What does the lock and key mechanism refer to in enzyme activity?

  It refers to the specific shape of the enzyme and substrate fitting together.
• What happens if the lock and key mechanism fails?

  There is always an alternative mechanism available.
• What is the role of RNA in relation to enzymes?

  RNA can act as a single strand in some enzymatic reactions.
• What is the outcome of an enzyme-catalyzed reaction?

  The enzyme remains unchanged after the reaction.
• What is the significance of temperature in enzyme activity?

  Temperature can affect the speed of chemical reactions.
• How do enzymes relate to the body's actions?

  Enzymes facilitate the body's biochemical processes.
• What is the role of enzymes in chemical reactions?

  Enzymes speed up chemical reactions.
• What are the key features of enzymes?

  • Enzymes control cell reactions
  • They are very specific
  • They remain unchanged after reactions
  • They can be affected by temperature
• What mechanisms do enzymes use to catalyze reactions?

  • Lock and key mechanism
  • Induced fit mechanism
  • Alternative pathways if the primary mechanism fails
• What effect does changing the temperature have on an enzyme-controlled reaction?

  It changes the rate of the reaction.
• Why does a higher temperature increase the rate of an enzyme-controlled reaction?

  Because substrate molecules move around more, increasing collision likelihood.
• What happens to an enzyme if the temperature gets too high?

  The enzyme's bonds break, changing the shape of the active site and denaturing it.
• What is the optimum temperature for most important human enzymes?

  About 37 °C.
• How does pH affect enzyme activity?

  Extreme pH levels interfere with the bonds holding the enzyme together.
• What is the optimum pH for pepsin?

  pH 2.
• Why is pepsin well-suited to the stomach environment?

  Because it works best at the acidic conditions of pH 2.
• How does enzyme concentration affect the rate of reaction?

  Increasing enzyme concentration increases the likelihood of substrate encounters.
• What happens when there are more enzyme molecules than substrate molecules?

  Adding more enzymes has no further effect on the reaction rate.
• How does substrate concentration affect the rate of reaction?

  Higher substrate concentration increases the reaction rate up to a point.
• What occurs when all active sites of enzymes are full?

  Adding more substrate makes no difference to the reaction rate.
• What is the relationship between enzyme shape and reaction activity?

  • The shape of the active site is crucial for substrate binding.
  • Any change in the active site shape stops the reaction.
• What might happen to enzyme A’s activity if the pH exceeds its optimum of 4?

  Enzyme A's activity may decrease due to changes in the active site shape.