photosynthesis

• What is produced during photosynthesis?

  Glucose and oxygen
• What is the primary function of chloroplasts in plant cells?

  They are the site of photosynthesis
• What pigment is primarily responsible for absorbing light in chloroplasts?

  Chlorophyll
• How is energy transferred to chloroplasts for photosynthesis?

  By light from the environment
• What type of reaction is photosynthesis classified as?

  Endothermic
• Write the word equation for photosynthesis.

  Light + carbon dioxide + water → glucose + oxygen
• Write the symbol equation for photosynthesis.

  $6CO₂ +$$6H₂O \rightarrow C₆H₁₂O₆ +$$6O₂$
• What are the five main uses of glucose in plants?

  • For respiration
  • Making cellulose
  • Making amino acids
  • Stored as oils or fats
  • Stored as starch
• How does glucose contribute to respiration in plants?

  It transfers energy for various processes
• What is cellulose used for in plants?

  To make strong plant cell walls
• How are amino acids formed in plants?

  By combining glucose with nitrate ions
• Why is starch a better storage form than glucose in plants?

  Starch is insoluble and does not draw in water
• What factors can limit the rate of photosynthesis?

  Light intensity, concentration of CO₂, and temperature
• What does it mean if a factor is a limiting factor in photosynthesis?

  It prevents photosynthesis from occurring any faster
• What is the limiting factor for photosynthesis at night?

  Light intensity
• What is the limiting factor for photosynthesis in winter?

  Temperature
• What can affect the amount of chlorophyll in a plant?

  Disease and environmental stress
• How does a lack of chlorophyll affect photosynthesis?

  It reduces the rate of photosynthesis
• What are the three important graphs related to the rate of photosynthesis?

  1. Effect of light intensity
  2. Effect of carbon dioxide concentration
  3. Effect of temperature
• How does light intensity affect the rate of photosynthesis?

  It increases the rate up to a certain point
• What happens to the rate of photosynthesis when light intensity is increased beyond a certain point?

  It levels off due to other limiting factors
• How can light intensity be changed in a lab experiment?

  By moving a lamp closer or further away from the plant
• What is the effect of too little carbon dioxide on photosynthesis?

  It slows down the rate of photosynthesis
• What happens when CO₂ is in plentiful supply?

  The limiting factor is usually temperature
• What is the effect of temperature on the enzymes involved in photosynthesis?

  Low temperatures slow down enzyme activity
• What happens to enzymes at high temperatures?

  They can be damaged
• At what temperature do enzymes begin to be damaged in plants?

  About 45 °C
• How can multiple limiting factors be represented in a graph?

  • By showing the effect of light intensity and temperature
  • By showing the effect of light intensity and CO₂ concentration
• What does the graph showing light intensity and temperature indicate?

  Both factors increase the rate of photosynthesis until one becomes limiting
• How does oxygen production relate to the rate of photosynthesis?

  It corresponds directly to the rate of photosynthesis
• What is the procedure for measuring the rate of photosynthesis using Canadian pondweed?

  1. Place a light source at a specific distance from the pondweed.
  2. Allow the pondweed to photosynthesize for a set time.
  3. Measure the length of the gas bubble in the capillary tube.
  4. Control variables like temperature and time.
  5. Repeat the experiment for accuracy.
• What is the relationship between light intensity and distance from the light source?

  They are inversely proportional
• What does the inverse square law state about light intensity?

  Light intensity decreases in proportion to the square of the distance
• Calculate the light intensity when the lamp is 10 cm from the pondweed using the inverse square law.

  $light\ intensity =$$\frac{1}{10^2} =$$0.01 \text{ au}$
• How can farmers create ideal conditions for plant growth in greenhouses?

  • Trap the Sun's heat
  • Use heaters in winter
  • Provide artificial light
  • Increase CO₂ levels
  • Control pests and diseases
  • Add fertilizers
• Why is it important for farmers to control the conditions in a greenhouse?

  To optimize plant growth and maximize crop yield
• What is a potential downside of artificially creating ideal conditions for plants?

  It can be costly
• What happens if a farmer provides more heat and light than plants need?

  It wastes money without benefiting plant growth