Photosynthesis

• What is the main topic of the video?

  Photosynthesis
• What is the purpose of photosynthesis?

  To make organic compounds like glucose
• Which organisms carry out photosynthesis?

  Plants and some photosynthetic bacteria
• What does the term "photo" in photosynthesis refer to?

  It relates to light
• What does the term "synthesis" in photosynthesis mean?

  Making food using light energy
• What is the summary equation for photosynthesis?

  Water + Carbon Dioxide → Glucose + Oxygen
• What is glucose classified as?

  A hexose sugar made of six carbons
• What is the structure of a generic plant cell?

  Cell wall, plasma membrane, vacuole, nucleus
• What are chloroplasts responsible for?

  They are the site of photosynthesis
• Why are chloroplasts green?

  Due to the presence of chlorophyll
• What are thylakoids?

  Small sacs with a membrane surrounding a lumen
• What is a granum?

  A stack of thylakoid membranes
• How are thylakoid membranes adapted for photosynthesis?

  They provide a large surface area
• What is the stroma in chloroplasts?

  A space containing enzymes for the Calvin cycle
• What is rubisco?

  An important enzyme in the Calvin cycle
• What is the light-dependent stage of photosynthesis?

  It relies on light to produce energy carriers
• What happens to water during the light-dependent stage?

  It is split into oxygen, hydrogen ions, and electrons
• What is photolysis?

  The splitting of water using light
• What enters photosystem 2 after photolysis?

  Electrons released from water
• What are the two types of photosystems?

  Photosystem 1 and Photosystem 2
• What is the role of accessory pigments?

  To absorb light and excite electrons
• What is chlorophyll a?

  The main pigment in photosystems
• What is photoionization?

  Excited electrons are released from chlorophyll
• What happens to electrons in the electron transport chain?

  They lose energy and pump protons
• What is chemiosmosis?

  Movement of protons through ATP synthase
• What does ATP synthase produce?

  ATP from ADP and inorganic phosphate
• What is the difference between cyclic and non-cyclic photophosphorylation?

  Cyclic uses the same electrons, non-cyclic does not
• What are the main stages of photosynthesis?

  1. Light-dependent stage

  • Water is split (photolysis)
  • Oxygen is released
  • ATP and NADPH are produced

  1. Light-independent stage (Calvin cycle)

  • Uses ATP and NADPH to synthesize glucose
• What are the roles of NADP+ in photosynthesis?

  • Accepts electrons from the electron transport chain
  • Combines with protons to form NADPH
  • NADPH is used in the Calvin cycle
• What are the accessory pigments in photosystems?

  • Chlorophyll b
  • Carotenoids
  • Xanthophyll
• What is the significance of the concentration gradient in the thylakoid lumen?

  • Drives the movement of protons back to the stroma
  • Powers ATP synthesis through ATP synthase
• What is the importance of the Calvin cycle?

  • Converts ATP and NADPH into glucose
  • Essential for plant growth and energy storage
• What has ADPH gained during the light-dependent stage?

  Hydrogen
• Why is ADPH considered reduced?

  It has gained hydrogen
• What are the products of the light-dependent stage of photosynthesis?

  ATP and NADPH
• What is the process called that produces ATP and NADPH?

  Non-cyclic photophosphorylation
• What happens to the excited electron in non-cyclic photophosphorylation?

  It is passed linearly along the electron transfer chain
• What can occur during times of stress in plants?

  Cyclic photophosphorylation
• What is the main purpose of cyclic photophosphorylation?

  To produce extra ATP
• What does cyclic photophosphorylation not produce?

  Reduced NADPH