Topic 4: Bioenergetics

• What is aerobic respiration?

  A form of respiration using oxygen
• What does aerobic respiration release energy from?

  From molecules like glucose
• What is the word equation for aerobic respiration?

  Glucose + Oxygen → Energy + Carbon Dioxide + Water
• What is anaerobic respiration?

  A form of respiration without using oxygen
• What does anaerobic respiration release energy from?

  From molecules like glucose
• What is the word equation for anaerobic respiration?

  Glucose → Energy + Lactic Acid
• What is cellular respiration?

  An exothermic reaction in living cells
• What is an inverse proportion?

  A relationship where one value increases, the other decreases
• What does the inverse square law describe?

  Light intensity decreases with distance squared
• What is the equation for the inverse square law?

  Light Intensity ∝ 1 / Distance²
• What is a limiting factor?

  A factor that limits the rate of a reaction
• What is metabolism?

  The sum of all reactions in a cell
• What is oxygen debt?

  The extra oxygen needed after exercise
• Why does the body need extra oxygen after exercise?

  To react with accumulated lactic acid
• What is photosynthesis?

  An endothermic reaction in plants
• What energy source is used in photosynthesis?

  Energy transferred from the environment by light
• What are the key differences between aerobic and anaerobic respiration?

  • Aerobic respiration uses oxygen; anaerobic does not.
  • Aerobic produces more energy than anaerobic.
  • Aerobic results in carbon dioxide and water; anaerobic produces lactic acid.
• What are the implications of limiting factors in biological reactions?

  • They can slow down metabolic processes.
  • They can affect growth and productivity.
  • They can lead to inefficient energy use.
• What is photosynthesis?

  The process by which plants make glucose
• What type of reaction is photosynthesis?

  It is an endothermic reaction
• What is the equation for photosynthesis?

  Carbon dioxide + water → glucose + oxygen

  
• What is the chemical symbol for carbon dioxide?

  CO​2
• What is the chemical symbol for oxygen?

  O​2
• What is the chemical symbol for water?

  H​2​O
• What factors affect the rate of photosynthesis?

  • Temperature
  • Light intensity
  • Carbon dioxide concentration
  • Amount of chlorophyll

  
• What is the chemical formula for glucose?


  C​6​H​12​O​6
• How does temperature affect the rate of photosynthesis?

  It increases until enzymes denature
• What happens to the rate of photosynthesis with increased light intensity?

  It generally increases for most plants
• How does carbon dioxide concentration affect photosynthesis?

  Higher concentration increases the rate

  
• What role does chlorophyll play in photosynthesis?

  It converts light energy to food
• What is a limiting factor in photosynthesis?

  An environmental condition restricting the rate
• How can the rate of photosynthesis be measured experimentally?

  By measuring oxygen production of a plant
• Describe the experimental setup to measure photosynthesis rate.

  • Pondweed in a sealed test tube with water
  • Capillary tube connected to a syringe
  • Lamp at a measured distance
  • Measure oxygen bubble movement
• What variables can be changed in the photosynthesis experiment?

  Temperature, time, light intensity
• Why is it important to control factors in the photosynthesis experiment?

  To ensure a valid experiment
• What does a graph with one limiting factor show?

  One line levels off with one factor
• What does a graph with two lines represent?

  Two limiting factors in two experiments
• How is light intensity measured?

  In lux
• What does the inverse square law describe?

  Light intensity decreases with distance squared
• If a lamp is 2 meters away, what is the light intensity?

  It is a quarter of its original value