Active Transport

• What process allows substances to be absorbed against a concentration gradient?

  Active transport
• How does active transport differ from diffusion?

  Active transport moves substances against the gradient
• What is the definition of diffusion?

  Net movement from high to low concentration
• What does the term "concentration gradient" refer to?

  Difference in concentration across a space
• What energy source is required for active transport?

  Energy from respiration
• Why can't sugars diffuse into the cell from the lumen?

  Higher concentration of sugars inside the cell
• What do mitochondria provide for active transport?

  Energy needed for the process
• What ions do root hair cells transport into plants?

  Magnesium ions
• Why do plants need magnesium?

  To make chlorophyll in leaves
• How do root hair cells use active transport?

  To move ions from soil into the cell
• What happens to ions after they enter root hair cells?

  They are transported to the xylem vessels
• What is the role of mitochondria in root hair cells?

  To provide energy for active transport
• What are the key differences between active transport and diffusion?

  • Active transport moves substances against the gradient
  • Diffusion moves substances down the gradient
  • Active transport requires energy from respiration
  • Diffusion does not require energy
• Describe the process of active transport in the human small intestine.

  1. Sugars like glucose are present in the lumen.
  2. Concentration of sugars is lower in the lumen than inside the cell.
  3. Active transport moves sugars into the cell.
  4. Sugars are then transported into the blood.
• Explain how root hair cells utilize active transport.

  1. Root hair cells absorb magnesium ions from soil.
  2. Concentration of ions is lower in soil than inside the cell.
  3. Active transport moves ions into the root hair cells.
  4. Ions are transported to xylem vessels for distribution.