Photosynthesis

• What process must a plant carry out to grow and survive?

  Photosynthesis
• Where does photosynthesis take place in a plant?

  In the leaves, specifically chloroplasts
• What is the process that allows plants to grow and survive?

  Photosynthesis
• Where does photosynthesis take place in a plant?

  In the leaves, specifically in the chloroplasts
• What is the pigment in chloroplasts that can absorb light?

  Chlorophyll
• What does the chlorophyll in chloroplasts use the absorbed light energy for?

  To convert carbon dioxide and water into glucose and oxygen
• What is the chemical equation for photosynthesis?

  $6\text{CO}_2 +$$6\text{H}_2\text{O} \rightarrow \text{C}_6\text{H}_{12}\text{O}_6 +$$6\text{O}_2$
• Where does the plant get the carbon dioxide and water needed for photosynthesis?

  Carbon dioxide diffuses into the leaves through the stomata, and water is taken up from the soil by the roots and transported to the leaves via the xylem
• What are the five main uses of the glucose produced during photosynthesis?

  1. Cellular respiration, 2. Making cellulose, 3. Making starch, 4. Making amino acids, 5. Making oils and fats
• Why is it important for plants to store starch?

  Starch is a more compact and insoluble form of glucose that can be stored for later use, especially during times when photosynthesis is not happening as much
• How does the rate of photosynthesis affect a plant's growth?

  A plant's growth rate is often dependent on how fast it can photosynthesize, as photosynthesis produces the glucose that is essential for the plant's growth and survival
• What are the four main factors that affect the rate of photosynthesis?

  Light intensity, temperature, carbon dioxide concentration, and the amount of chlorophyll
• What are the main steps of the photosynthesis process?

  1. Light absorption by chlorophyll
  2. Light-dependent reactions: water splitting, electron excitation
  3. Electron transport chain: ATP and NADPH production
  4. Calvin cycle (light-independent reactions):

  • CO2 fixation
  • Reduction of fixed carbon
  • Regeneration of RuBP

  1. Glucose and other carbohydrates synthesized
• What do plants need to carry out photosynthesis?

  Light, carbon dioxide, temperature, chlorophyll
• How does chlorophyll affect photosynthesis?

  Less chlorophyll means less photosynthesis
• What can cause variations in chlorophyll levels in plants?

  Disease, environmental stress, lack of nutrients
• What are the limiting factors for photosynthesis?

  Light, carbon dioxide, temperature
• What is plotted on the x-axis of photosynthesis graphs?

  Light, carbon dioxide, temperature
• What happens to the rate of photosynthesis as light intensity increases?

  The rate of photosynthesis increases
• What does it mean when the graph of photosynthesis plateaus?

  Another factor is limiting photosynthesis
• How does carbon dioxide concentration affect photosynthesis?

  Higher concentration increases the rate
• What happens to the rate of photosynthesis as temperature increases?

  It rises until enzymes denature
• At what temperature do enzymes involved in photosynthesis fully denature?

  About 45 degrees Celsius
• What does a graph with two curves represent in photosynthesis experiments?

  Different experiments with varying conditions
• How can comparing two curves on a graph indicate a limiting factor?

  It shows which condition affects photosynthesis
• What is the benefit of using greenhouses for farmers?

  They trap heat and increase temperature
• How do farmers provide artificial light for photosynthesis?

  By using artificial lighting systems
• What is one method farmers use to increase carbon dioxide levels?

  Pumping carbon dioxide into greenhouses
• What is a paraffin heater used for in greenhouses?

  It releases heat and carbon dioxide
• Why do farmers use fertilizers?

  To ensure plants have essential minerals
• What must farmers consider when increasing crop yield?

  The cost versus the extra yield gained
• What are the main factors affecting the rate of photosynthesis?

  • Light intensity
  • Carbon dioxide concentration
  • Temperature
  • Chlorophyll levels
• How do farmers optimize conditions for photosynthesis in greenhouses?

  • Trap heat to increase temperature
  • Provide artificial light
  • Pump in carbon dioxide
  • Use fertilizers and pesticides
• How do graphs help in understanding photosynthesis?

  • Show relationships between factors
  • Indicate limiting factors
  • Compare different experimental conditions