Photosynthesis and limiting factors

• What is the process by which plants convert light energy into chemical energy?

  Photosynthesis
• Why is photosynthesis considered an endothermic reaction?


  Because it absorbs light energy to convert carbon dioxide and water into glucose and oxygen
• Where does photosynthesis take place in plants?


  In the leaves, specifically in chloroplasts
• What pigment inside chloroplasts absorbs light energy?

  Chlorophyll
• What is the chemical equation for photosynthesis?


  Carbon dioxide + water → Glucose + oxygen
• What is the balanced equation for photosynthesis in terms of molecules?


  CO2 + 6H2O → C6H12O6 + 6O2
• What is required for the photosynthesis reaction to take place?


  Light energy
• What are the five uses of glucose in plants?

  • Cellulose for cell walls
  • Respiration for energy
  • Oils and fats
  • Protein synthesis
  • Stored as starch
• How does the inverse square law relate to light intensity and distance?


  Light intensity is inversely proportional to the square of the distance
• What happens to the rate of photosynthesis as light intensity increases?


  It increases until it reaches a plateau due to a limiting factor
• What effect does carbon dioxide concentration have on photosynthesis?


  More CO2 increases photosynthesis until it plateaus due to a limiting factor
• How does temperature affect the rate of photosynthesis?


  Higher temperatures increase the rate until enzymes denature at high temperatures
• At what temperature do enzymes begin to denature, affecting photosynthesis?


  45℃
• What is the optimal temperature for the rate of photosynthesis mentioned in the material?


  25℃
• How can farmers artificially create optimal conditions for photosynthesis?


  • Use greenhouses to trap heat
  • Increase CO2 concentration
  • Use artificial light
  • Employ paraffin heaters for heat and CO2
• What is a benefit of using greenhouses for plants?


  They prevent pests and pathogens from easily accessing the plants
• What are the purposes of fertilizers and pesticides in agriculture?


  • Fertilizers provide essential minerals
  • Pesticides kill unwanted bugs
• What is the main topic discussed in this material?

  Bioenergetics
• What process do plants use to produce glucose?

  Photosynthesis
• What is the primary purpose of photosynthesis in plants?


  To produce glucose
• In what ways do plants use glucose?


  • Energy source for cellular respiration
  • Building blocks for growth and development
  • Storage as starch
  • Synthesis of other organic compounds
  • Contribution to plant structure (cellulose)
• What are limiting factors in the context of photosynthesis?


  Factors that affect the rate of photosynthesis
• Name one limiting factor of photosynthesis.


  Temperature
• How many marks is Q1 worth in the exam?


  2 marks
• How many limiting factors of photosynthesis should be named in Q2?


  Three limiting factors
• What are the products of photosynthesis?


  • Glucose
  • Oxygen
• What is the significance of the phrase "Now you'll have something to bore the great-grandkids with" in the context of the study material?


  It suggests the long-term importance of understanding photosynthesis.
• Why is it important to study limiting factors in photosynthesis?


  To understand how they affect the efficiency of photosynthesis.
• What type of reaction is photosynthesis?


  Endothermic reaction
• How is energy transferred to chloroplasts during photosynthesis?


  By light from the environment
• What are the reactants of the photosynthesis reaction?


  Carbon dioxide and water
• What are the products of the photosynthesis reaction?


  Glucose and oxygen
• What is the chemical equation for photosynthesis?


  6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
• What are the four uses of glucose in plants?

  1. Respiration – energy is transferred from glucose.
  2. Strengthening cell walls – glucose is converted into cellulose.
  3. Protein synthesis – glucose and nitrate ions are used to make amino acids.
  4. Energy storage – glucose is turned into lipids or insoluble starch.
• How is glucose used in respiration in plants?


  Energy is transferred from glucose
• What is glucose converted into for strengthening cell walls?


  Cellulose
• What do glucose and nitrate ions produce in plants?


  Amino acids
• How is glucose stored in plants?


  As lipids or insoluble starch