Photosynthetic reaction

• What is photosynthesis?

  Process converting CO₂ and water into glucose
• Why is photosynthesis considered an endothermic reaction?

  It requires an input of energy from sunlight
• What is the word equation for photosynthesis?

  Carbon dioxide + Water → Glucose + Oxygen
• What is the symbol equation for photosynthesis?

  6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
• How is carbon dioxide taken in by plants?

  Through the stomata in leaves
• How is water absorbed by plants?

  By roots from the soil, transported through xylem
• What is glucose used for in plants?

  For energy or stored as starch
• What is released as a waste product during photosynthesis?

  Oxygen
• Where does photosynthesis primarily occur in plants?

  In chloroplasts, mainly in palisade mesophyll
• What pigment in chloroplasts absorbs light energy?

  Chlorophyll
• Why do leaves have a large surface area for photosynthesis?

  To capture more light energy
• What are the two main stages of photosynthesis?

  1. Light-Dependent Stage

  • Takes place in thylakoids
  • Requires light
  • Splits water into oxygen, hydrogen ions, and electrons
  • Produces ATP

  
  

  1. Light-Independent Stage (Calvin Cycle)

  • Takes place in stroma
  • Does not require light
  • Uses CO₂ to produce glucose
• What happens during the light-dependent stage of photosynthesis?

  Light energy splits water into oxygen and ATP
• What is photolysis in photosynthesis?

  Splitting water molecules into oxygen and ions
• What is produced as a byproduct of the light-dependent stage?

  Oxygen
• What is the role of ATP in photosynthesis?

  Powers the light-independent stage reactions
• What does the light-independent stage use to produce glucose?

  CO₂, hydrogen ions, and ATP
• What is the definition of photosynthesis?

  Photosynthesis is the process by which green plants, algae, and some bacteria use light energy to convert carbon dioxide and water into glucose and oxygen.
• What is the word equation for photosynthesis?

  Carbon dioxide + Water → Glucose + Oxygen
• What is the symbol 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 photosynthesis take place in a plant cell?

  Photosynthesis takes place in the chloroplasts, mainly in the palisade mesophyll cells of the leaves.
• What is the role of chlorophyll in photosynthesis?

  Chlorophyll is a green pigment in chloroplasts that absorbs light energy to power the photosynthesis process.
• What are the two main stages of photosynthesis?

  The two main stages of photosynthesis are the light-dependent stage and the light-independent (Calvin cycle) stage.
• What happens in the light-dependent stage of photosynthesis?

  In the light-dependent stage, light energy is absorbed by chlorophyll, which is used to split water molecules into oxygen, hydrogen ions, and electrons, releasing oxygen as a byproduct and producing ATP to power the next stage.
• What happens in the light-independent (Calvin cycle) stage of photosynthesis?

  In the light-independent (Calvin cycle) stage, the hydrogen ions and ATP produced in the light-dependent stage are used to convert carbon dioxide into glucose, with some glucose used for respiration and excess stored as starch.
• What are the four main factors that can limit the rate of photosynthesis?

  The four main factors that can limit the rate of photosynthesis are light intensity, carbon dioxide concentration, temperature, and chlorophyll amount.
• How does light intensity affect the rate of photosynthesis?

  Increasing light intensity increases the rate of photosynthesis, but only up to a certain point, after which another factor becomes limiting and further increases in light have no effect.
• How does carbon dioxide concentration affect the rate of photosynthesis?

  Increasing carbon dioxide concentration increases the rate of photosynthesis, up to a certain limit, as carbon dioxide is an essential reactant for the process.
• How does temperature affect the rate of photosynthesis?

  Increasing temperature increases the rate of photosynthesis, as enzymes work faster, but above 45°C the enzymes denature and photosynthesis stops.
• How does the amount of chlorophyll affect the rate of photosynthesis?

  Decreasing the amount of chlorophyll, such as due to disease, deficiency, or environmental stress, reduces light absorption and slows the rate of photosynthesis.
• What are the five main ways plants use the glucose produced during photosynthesis?

  Plants use the glucose produced during photosynthesis for respiration, storing as starch, making cellulose, making amino acids, and making lipids.
• How does the experimental setup to investigate the effect of light intensity on photosynthesis using pondweed work?

  1. Place pondweed (Elodea) in a beaker of water
  2. Add sodium hydrogen carbonate (source of CO2)
  3. Use a lamp at different distances from the pondweed
  4. Count the bubbles of oxygen produced per minute or collect gas in a syringe
  5. Closer lamp = More bubbles (higher light intensity = faster photosynthesis)
  6. After a certain point, increasing light has no further effect (another limiting factor is in play)