organisation and digestion -B3

• What is the purpose of bile in digestion?

  To neutralize stomach acid and emulsify fats
• What are enzymes?

  Biological catalysts that speed up chemical reactions
• What is the lock and key principle in enzyme activity?

  Enzymes are specific and only work with certain substrates
• What happens to an enzyme at its optimum temperature?

  The rate of enzyme activity is maximized
• How do you determine the optimum pH for an enzyme?

  By mixing amylase with starch at different pH levels and timing the reaction
• What color does iodine turn in the presence of starch?

  From brown to black
• What is a tissue?

  A group of cells of the same type
• What is an organ?

  A group of tissues that work together
• What is the function of the digestive system?

  To break down food and absorb nutrients
• What is the function of proteins in digestion?

  They are broken down into amino acids
• What happens when starch is tested with iodine?

  It turns black
• What color does glucose turn when tested with Benedict's solution?

  Orange/red precipitate
• What is the role of saliva in digestion?

  It contains enzymes that begin the digestion process
• What is the role of the stomach in digestion?

  It churns food and releases acid and enzymes
• What is the function of the small intestine?

  It absorbs products of digestion
• What is the role of bile produced by the liver?

  It helps in the digestion of fats
• What is amylase?

  An enzyme that breaks down starch
• What is lipase?

  An enzyme that digests fats
• What is protease?

  An enzyme that digests proteins
• What is the enzyme-substrate complex?

  • Formed when an enzyme binds to its substrate
  • Enzyme has an active site that is complementary to the substrate shape
  • Facilitates the conversion of substrates into products
• What factors affect enzyme activity?

  Temperature, pH, enzyme concentration, and substrate concentration
• What happens to enzymes at high temperatures?

  They denature
• What is the optimum pH for enzymes?

  It is the pH at which the enzyme activity is highest
• How does increasing enzyme concentration affect the rate of reaction?

  It increases the rate of reaction
• How does increasing substrate concentration affect the rate of reaction?

  It increases the rate of reaction until all enzymes are saturated
• What is the relationship between enzyme concentration and reaction rate?

  Higher enzyme concentration generally increases reaction rate
• What is the effect of pH on enzyme activity?

  Enzymes have an optimum pH for maximum activity
• What happens to enzyme activity when the pH is too high or too low?

  Enzyme activity decreases and may denature
• How do temperature and pH interact to affect enzyme activity?

  Both must be within optimal ranges for maximum enzyme activity
• What is the effect of substrate concentration on enzyme activity?

  Increased substrate concentration increases reaction rate until saturation
• What is the steady state in enzyme kinetics?

  It is when the rate of formation of the enzyme-substrate complex equals the rate of its breakdown