Decay

• What is the main focus of the practical described in the video?

  Investigating temperature's effect on milk decay
• Why does milk sour when left at room temperature?

  Bacteria produce acidic molecules during decay
• What enzyme is used to model decay in this experiment?

  Lipase
• What is the process of modeling decay in this practical?

  • Use lipase to break down fat
  • Measure pH change in milk
  • Observe color change with indicator
• What is the initial color of the solution after adding sodium carbonate and the indicator?

  Purple
• What does the color change from purple to yellow indicate?

  The solution has become acidic
• What is the independent variable in this experiment?

  Temperature
• What is the dependent variable in this experiment?

  Time taken for milk to turn yellow
• What are the control variables in this experiment?

  Volumes of all solutions used
• Why is it important to use a clean test tube for each experiment?

  To avoid triggering reactions prematurely
• How can sharing data with other groups help in this experiment?

  It allows for calculating a mean result
• What happens to enzyme activity at different temperatures?

  • Slow at low temperatures
  • Fastest at optimum temperature
  • Slows down or stops at high temperatures
• What is the optimum temperature for enzyme reactions?

  The temperature at which reactions are fastest
• What happens to enzymes at temperatures higher than optimum?

  They denature and stop functioning
• How do decomposing microorganisms behave in warm conditions?

  They work faster but not in hot conditions
• What is the effect of high temperatures on decomposing microorganisms?

  Enzymes denature and stop working
• What type of questions can be expected on this practical?

  Questions related to the required practical