photosynthesis

• What is the process by which plants transport sugars?

  Translocation
• How do plants make their own sugars?

  Through photosynthesis in the leaves
• What are Phloem cells primarily responsible for?

  Transporting sugars in plants
• What are Phloem tubes made of?

  Phloem cells arranged end to end
• What do the small pores between phloem cells allow for?

  Movement of cell sap, a liquid mixture
• What can sugars be used for once transported to cells?

  For energy or stored for later
• In which directions can the Phloem tubes transport substances?

  Up or down the plant
• What are xylem tubes made of?

  Dead xylem cells with no ends
• What is the role of xylem tubes?

  Transporting water and mineral ions
• How are xylem tubes strengthened?

  With a material called lignin
• What drives the movement of water through a plant?

  Evaporation of water from the leaves
• What is transpiration?

  Evaporation of water from leaves
• What is the transpiration stream?

  The chain of water molecules moving up
• What factors influence the rate of transpiration?

  Light intensity, temperature, air flow, humidity
• How does light intensity affect transpiration?

  Higher light increases photosynthesis and transpiration
• What happens to transpiration at night?

  It decreases due to closed stomata
• How does temperature affect the rate of transpiration?

  Warmer temperatures increase evaporation rates
• What happens to the concentration gradient of water in leaves?

  Higher inside than outside, promoting diffusion
• How does high air flow affect transpiration?

  It increases the rate by blowing water away
• How does humidity affect transpiration?

  Higher humidity decreases the rate of transpiration
• What are the main components of plant mass transport systems?

  • Translocation: transport of sugars
  • Transpiration: transport of water
  • Phloem tubes: transport sugars
  • Xylem tubes: transport water and minerals
• What are the factors affecting transpiration rates in plants?

  1. Light intensity
  2. Temperature
  3. Air flow
  4. Humidity
• How does the structure of Flo and xylem tubes relate to their functions?

  • Phloem tubes: living cells, transport sugars
  • Xylem tubes: dead cells, transport water and minerals
• What is the relationship between transpiration and photosynthesis?

  • Transpiration: water loss for gas exchange
  • Photosynthesis: requires CO2, facilitated by open stomata
• What are the different levels of organization in plants?

  Cells, tissues, organs, organ systems
• What is the function of the organ system formed by leaves, stems, and roots?

  Transport of substances around the plant
• What is the primary function of leaves?

  Photosynthesis
• What do leaves require for photosynthesis?

  Carbon dioxide and water
• How is water transported to the leaves?

  By the roots and xylem
• How does carbon dioxide enter the leaf?

  Through stomata from the outside air
• What are stomata?

  Little holes for gas exchange
• Where are stomata primarily located on a leaf?

  On the lower epidermis
• What is the spongy mesophyll tissue's role in a leaf?

  Facilitates gas diffusion
• Where does most photosynthesis occur in the leaf?

  In the palisade mesophyll layer
• What do palisade cells contain that aids in photosynthesis?

  Chloroplasts
• Why are the upper epidermis cells almost transparent?

  To allow sunlight to pass through
• How are sugars transported in the plant after photosynthesis?

  By the phloem
• What is the main problem leaves face regarding water?

  Water loss
• How does the xylem contribute to leaf function?

  Brings water up from the roots
• What is the function of the waxy cuticle on leaves?

  Prevents water loss