Photosynthesis Overview

• What are the three raw materials of photosynthesis?

  Carbon dioxide, water, and light
• What are the products of photosynthesis?

  Glucose and oxygen
• What is the chemical equation for photosynthesis?

  6CO2 + 6H2O → C6H12O6 + 6O2
• How is the leaf adapted to carry out photosynthesis?

  Leaves are thin and have a large surface area
• Why do leaves have a transparent cuticle and epidermis?

  To allow light through to mesophyll cells
• What is the purpose of the upper epidermis in leaves?

  Protects inner tissues and allows light through
• How are upper mesophyll cells adapted for photosynthesis?

  They are long, narrow, and packed with chloroplasts
• Why are stomata located near mesophyll cells?

  To facilitate gaseous exchange
• What can stomata do to regulate transpiration?

  They can open and close
• What is the function of air spaces in the lower mesophyll layer?

  Allow rapid diffusion of gases
• What creates air spaces in the mesophyll layer?

  Loosely packed cells
• What is the role of xylem in leaves?

  Transports water to leaf cells
• What is the role of phloem in leaves?

  Transports sugars produced in photosynthesis
• What are the adaptations of leaves for photosynthesis and their purposes?

  • Thin leaf: Short diffusion distance for gases
  • Large surface area: Captures more light
  • Minimal overlapping: Prevents shading of lower leaves
  • Transparent cuticle: Allows light to reach mesophyll
  • Upper epidermis: Protects tissues and allows light
  • Palisade mesophyll: Maximizes light absorption
  • Spongy mesophyll: Facilitates gas diffusion
  • Stomata: Allows CO₂ diffusion into cells
  • Xylem vessels: Transports water
  • Phloem vessels: Transports sugars
• What are the two main stages of photosynthesis?

  Light-dependent and light-independent reactions
• Where does the light-dependent reaction occur in the chloroplast?

  Thylakoid membranes
• What is produced during the light-dependent reaction?

  Reduced NADP, ATP, and oxygen
• What is the light-independent reaction also known as?

  The Calvin Cycle
• What is the main sugar produced in the light-independent reaction?

  Glucose
• What gas is released as a by-product of the light-dependent reaction?

  Oxygen
• What connects grana together inside a chloroplast?

  Inter-granal lamellae
• What is the purpose of the grana structure in chloroplasts?

  Increases surface area for reactions
• Why is glucose converted into sucrose before translocation?

  Sucrose is less reactive and more stable
• What are the raw materials of photosynthesis?

  Carbon dioxide and water
• What are the products of photosynthesis?

  Glucose and oxygen
• What is the role of chlorophyll in photosynthesis?

  Captures light energy
• How does photosynthesis contribute to energy transfer in ecosystems?

  It converts light energy into chemical energy
• What are the main stages of photosynthesis?

  1. Capturing light energy by chlorophyll
  2. Light-dependent reaction (thylakoid membranes)
  3. Light-independent reaction (Calvin Cycle in stroma)
• What happens during photolysis in the light-dependent reaction?

  Water splits into protons, electrons, and O2
• What is the function of the stroma in chloroplasts?

  Site of the light-independent reaction
• What is the significance of the law of conservation of energy in photosynthesis?

  Energy is transformed, not created or destroyed
• How do non-photosynthetic organisms obtain energy from plants?

  By consuming glucose produced in photosynthesis
• What is the main purpose of photosynthesis?

  To convert light energy into chemical energy
• What is the role of ATP in photosynthesis?

  Provides energy for cellular processes
• What is the relationship between photosynthesis and cellular respiration?

  Photosynthesis produces glucose used in respiration
• How does the structure of chloroplasts facilitate photosynthesis?

  Grana increase surface area for reactions
• What is the significance of starch grains in chloroplasts?

  Store glucose produced during photosynthesis
• What is the role of light in photosynthesis?

  Provides energy for the light-dependent reactions
• How do chloroplasts capture light energy?

  Through chlorophyll pigments in thylakoids
• What is the importance of the Calvin Cycle in photosynthesis?

  Produces sugars from carbon dioxide