Active Transport

• What does diffusion involve in terms of substance movement?

  Substances move from a high concentration to a low concentration.
• Does diffusion require energy?

  No, diffusion does not require energy.
• What is the definition of active transport?

  • Substances move from a low concentration to a high concentration
  • Requires energy
• What is the role of xylem in plants?

  Xylem transports water and minerals from the roots to the leaves.
• What is the role of phloem in plants?

  Phloem transports sugars from the leaves to other parts of the plant.
• How does lignin help the xylem?

  Lignin makes the xylem waterproof and strong.
• What are the steps of transpiration in plants?

  1. Water evaporates and diffuses from the leaf (stomata).
  2. Water passes back into the leaf through xylem vessels by osmosis.
  3. Water is pulled upwards through the xylem tissue.
  4. This is replaced by water entering from the root tissue.
  5. Water enters root hair cells by osmosis.
• What is the function of plant roots?

  Plant roots absorb water and minerals from the soil.
• What is the equation for photosynthesis?

  6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂
• How do minerals like magnesium and calcium get into the plant?

  Minerals enter the plant through the roots from the soil.
• What does osmosis involve in terms of water movement?

  Water moves from a high water potential to a low water potential.
• Does osmosis require energy?

  No, osmosis does not require energy.
• What is the definition of active transport?

  Active transport is the movement of substances from a low concentration to a high concentration.
• Where does the energy for active transport come from?

  The energy for active transport comes from ATP.
• What is translocation in plants?

  • Movement of sugars from the leaves to other parts of the plant
  • Source: where sugars are produced
  • Sink: where sugars are delivered to
• What is the function of guard cells in plants?

  Guard cells open and close the stomata to regulate gas exchange.
• How do guard cells open and close?

  Water enters or leaves the guard cells by osmosis, causing them to swell or shrink.
• Why are there more stomata on the lower surface of a leaf?

  More stomata on the lower surface reduce water loss and protect from direct sunlight.
• How does potassium affect guard cells?

  Potassium levels increase in guard cells, causing them to swell and open the stomata.
• How does water enter the plant?

  Water enters the plant through root hair cells by osmosis.
• How does phosphate enter the plant?

  Phosphate enters the plant through active transport in the roots.
• How does magnesium enter the plant?

  Magnesium enters the plant through active transport in the roots.
• What are the three main processes of substance movement in plants?

  • Diffusion
  • Osmosis
  • Active transport