photosynthesis

Cards (31)

  • What are autotrophs?

    Organisms that make their own food
  • What do photoautotrophs do?

    They transform sunlight energy into chemical energy using CO2 and H2O
  • How do chemoautotrophs obtain their nutrients?

    They obtain inorganic nutrients and combine them with CO2 to make organic food
  • What are heterotrophs?

    Consumers that obtain organic food by eating other organisms or their by-products
  • Which organisms make the majority of O2 on our planet?
    Cyanobacteria
  • What is the major site of photosynthesis in plants?

    Leaves
  • What is the function of stomata in plants?

    They facilitate gas exchange
  • What is the organelle where photosynthesis occurs?

    Chloroplast
  • What are the main components of a chloroplast?

    Double membrane, thylakoids, grana, stroma, and chlorophyll
  • What is the chemical equation for photosynthesis?

    6 CO2 + 6 H2O + Light energy → C6H12O6 + 6 O2
  • What type of process is photosynthesis?

    It is a redox process
  • What happens to water during photosynthesis?

    Water is oxidized, and electrons are transferred to CO2
  • What are the two major steps of photosynthesis?

    1. Light reactions: Excite electrons in chlorophyll, produce NADPH and ATP
    2. Calvin cycle: Fix carbon into organic molecules like glucose
  • What is the visible spectrum?

    The array of colors from red to violet that can be separated using a prism
  • What is the role of pigments in photosynthesis?

    Pigments absorb visible light and reflect certain colors
  • What are the two most common types of chlorophyll?

    Chlorophyll a and Chlorophyll b
  • What are accessory pigments?

    They absorb colors that chlorophyll a cannot and help capture more light energy
  • What was the conclusion of Engelmann's experiment?

    Violet-blue and red light are most effective in driving photosynthesis
  • What are the phases of the Calvin cycle?

    1. Carbon fixation: CO2 attached to RuBP
    2. Reduction: Electrons from NADPH reduce to G3P
    3. Regeneration: G3P rearranged to RuBP
  • What is chemiosmosis?

    The process of making ATP using a proton concentration gradient across membranes
  • What is the role of ATP synthase in chloroplasts?

    It uses the proton-motive force to make ATP
  • How do light reactions and the Calvin cycle differ?

    • Light reactions: Convert light energy to ATP and NADPH, release O2
    • Calvin cycle: Use ATP and NADPH to convert CO2 to G3P
  • How do chloroplasts and mitochondria generate ATP?

    Both use chemiosmosis but different energy sources
  • What is the spatial organization of chemiosmosis in chloroplasts?

    It occurs across the thylakoid membrane and stroma
  • What is the main product of the Calvin cycle?

    G3P (glyceraldehyde 3-phosphate)
  • What happens to G3P produced in the Calvin cycle?

    It can be used to make glucose and other organic compounds
  • What is cyclic electron flow?

    An alternative cycle when ATP is deficient, using Photosystem I only
  • What are the key differences between light reactions and Calvin cycle reactions?
    • Light reactions: Occur in thylakoid membranes, produce ATP and NADPH, split water
    • Calvin cycle: Occur in stroma, use ATP and NADPH to convert CO2 to G3P
  • What is the role of RuBP in the Calvin cycle?
    RuBP is the molecule to which CO2 is attached during carbon fixation
  • What is the significance of the porphyrin ring in chlorophyll?

    It is the light-absorbing "head" of the molecule
  • How does the structure of chlorophyll a differ from chlorophyll b?
    A slight difference in molecular structure allows them to absorb different colors of light