Photosynthesis

• What shape are chloroplasts?

  Oval-shaped
• Where do chloroplasts mainly occur in plants?

  In the leaves
• What surrounds a chloroplast?

  A double membrane
• What fills the chloroplast?

  The stroma
• What are the disc-shaped membranes in the stroma called?

  Lamellae or thylakoids
• What do lamellae form when stacked?

  Grana
• What pigment is embedded in the lamellae?

  Chlorophyll
• How are two grana connected?

  By a membrane known as the intergranum
• What does the stroma contain besides enzymes?

  Starch grains, oil droplets, and ribosomes
• What process occurs in the chloroplasts?

  Photosynthesis
• What is built up during photosynthesis?

  Energy-rich carbohydrates (glucose)
• What does chlorophyll absorb during photosynthesis?

  Radiant energy from the sun
• What are the raw materials required for photosynthesis?

  Water (H₂O) and carbon dioxide (CO₂)
• What is released as a by-product of photosynthesis?

  Oxygen (O₂)
• What is the overall equation for photosynthesis in words?

  • Carbon dioxide + water + sunlight → Glucose + oxygen
• What is the chemical equation for photosynthesis?

  • $CO_2 +$$H_2O +$$\text{Radiant Energy} \rightarrow C_6H_{12}O_6 +$$O_2$
• What are the two phases of photosynthesis?

  • Light Phase (Photolysis)
  • Dark Phase (Calvin Cycle)
• Where does the light phase of photosynthesis occur?

  In the grana of the chloroplast
• What happens to water during the light phase?

  It is split into oxygen and hydrogen molecules
• What are the products of the light phase?

  Hydrogen atoms, energy (ATP), and oxygen
• What binds to NADP during the light phase?

  Energized hydrogen atoms
• Where does the Calvin cycle occur?

  In the stroma of the chloroplast
• What is needed for the Calvin cycle to function?

  Hydrogen and ATP energy from the light phase
• What is produced in the Calvin cycle?

  Glucose
• What happens to NADP and ADP after the Calvin cycle?

  They go back to the grana
• What happens to glucose after photosynthesis?

  • Converted into starch (storage)
  • Absorbs nitrogen from soil as nitrates (NO₃)
  • Forms amino acids from glucose and nitrogen
  • Excess glucose converted into fats and oils
• What is the importance of photosynthesis?

  • Maintains carbon-oxygen balance in the atmosphere
  • Provides radiant energy for heterotrophs
  • Fossil fuels originate from photosynthesizing plants
• What does a blue/black color indicate in a starch test?

  Presence of starch and thus photosynthetic activity
• What factors affect photosynthesis?

  • Light
  • Temperature
  • Chlorophyll
  • Carbon dioxide