Photosynthesis

• What is the primary purpose of photosynthesis in plants?

  To produce glucose using light energy
• What are the two main stages of photosynthesis?

  Light dependent and light independent stages
• What factors determine the rate of photosynthesis?

  Carbon dioxide concentration, light intensity, and temperature
• Where does photosynthesis occur in plant cells?

  In the chloroplasts
• How are chloroplasts adapted for photosynthesis?

  They contain grana with thylakoid membranes for chlorophyll attachment
• What is the role of ATP synthase in chloroplasts?

  To synthesize ATP from ADP and Pi
• What happens during photoionization in the light-dependent reaction?

  Electrons in chlorophyll become excited by photons
• What is the product of photolysis in the light-dependent reaction?

  Oxygen, protons, and electrons
• What is the purpose of the proton gradient in the thylakoid space?

  To drive ATP synthesis through ATP synthase
• What enzyme is required for carbon dioxide fixation in the light-independent reaction?

  Rubisco
• What is the role of reduced NADP in the light-independent reaction?

  To reduce glycerate-3-phosphate to triose phosphate
• How many turns of the Calvin Cycle are needed to produce one molecule of glucose?

  6 turns
• What is the main difference between aerobic and anaerobic respiration?

  Aerobic respiration requires oxygen, anaerobic does not
• Where does glycolysis occur in the cell?

  In the cytoplasm
• What are the products of glycolysis?

  2 pyruvate, 2 ATP, and 2 NADH
• What happens to pyruvate in anaerobic respiration?

  It is converted into lactate
• What is the role of the link reaction in aerobic respiration?

  To convert pyruvate into acetyl CoA
• Where does the Krebs cycle take place?

  In the mitochondrial matrix
• What are the products of the Krebs cycle per glucose molecule?

  2 ATP, 6 NADH, 2 FADH2, and 4 CO2
• What are the key steps in the light-dependent reaction of photosynthesis?

  1. Photoionization: Chlorophyll absorbs light, exciting electrons
  2. Photolysis: Water splits into oxygen, protons, and electrons
  3. Electron transport chain: Electrons move, pumping protons into thylakoid space
  4. Proton gradient drives ATP synthesis via ATP synthase
  5. Electrons reduce NADP to form NADPH
• What are the key steps in the light-independent reaction (Calvin Cycle)?

  1. Carbon dioxide fixation: CO2 + RuBP → glycerate-3-phosphate
  2. Reduction: Glycerate-3-phosphate → triose phosphate using NADPH and ATP
  3. Regeneration of RuBP: Triose phosphate → RuBP using ATP
  4. Organic molecule production: Triose phosphate → glucose
• What are the key steps in glycolysis?

  1. Glucose is phosphorylated to form glucose-6-phosphate
  2. Glucose-6-phosphate is converted to fructose-6-phosphate
  3. Fructose-6-phosphate is phosphorylated to form fructose-1,6-bisphosphate
  4. Fructose-1,6-bisphosphate splits into two 3-carbon molecules
  5. 3-carbon molecules are converted to pyruvate, producing ATP and NADH
• What are the key steps in the Krebs cycle?

  1. Acetyl CoA combines with oxaloacetate to form citrate
  2. Citrate is converted to isocitrate
  3. Isocitrate is oxidized to α-ketoglutarate, producing NADH and CO2
  4. α-ketoglutarate is oxidized to succinyl-CoA, producing NADH and CO2
  5. Succinyl-CoA is converted to succinate, producing ATP
  6. Succinate is oxidized to fumarate, producing FADH2
  7. Fumarate is converted to malate
  8. Malate is oxidized to oxaloacetate, producing NADH
• What is the role of chloroplast DNA and ribosomes in photosynthesis?

  To synthesize proteins for the light-dependent reaction
• How is the proton gradient formed in the thylakoid space?

  By pumping protons into the thylakoid space
• What is the role of stalked particles in the thylakoid membrane?

  To facilitate proton movement across the membrane
• How is RuBP regenerated in the Calvin Cycle?

  Using 5 molecules of triose phosphate
• What intermediate hexose sugar is formed in the Calvin Cycle?

  Fructose 1,6-bisphosphate
• What happens to lactate in anaerobic respiration?

  It is converted back to pyruvate in the liver
• What are the products of the link reaction per glucose molecule?

  2 acetyl CoA and 0 ATP
• What is the starting molecule in the Krebs cycle?

  A 4-carbon molecule that accepts acetate