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 concentration gradient, while diffusion moves them down the gradient
• What is required for active transport to occur?

  Energy from respiration
• What is a concentration gradient?

  A concentration gradient is the difference in concentration of particles between two areas
• In which part of the human body is active transport used to absorb sugars like glucose?

  In the cells lining the small intestine
• Why can't sugars diffuse into the cells lining the small intestine?

  Because the concentration of sugars is lower in the lumen than inside the cell
• What organelle provides the energy needed for active transport in cells?

  Mitochondria
• What ions do root hair cells transport into plants using active transport?

  Magnesium ions
• Why do plants need magnesium ions?

  To make chlorophyll in the leaves
• How do root hair cells transport ions from the soil into the plant?

  By using active transport to move ions against the concentration gradient
• What happens to the ions once they are inside the root hair cells?

  They are transported to the xylem vessels and moved to the leaves
• What is the lumen in the context of the small intestine?

  The cavity where food is digested
• What is the significance of having many mitochondria in cells that perform active transport?

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

  • Active transport moves substances against the concentration gradient, while diffusion moves them down.
  • Active transport requires energy from respiration, while diffusion does not.
• What are two examples of active transport in biology?

  1. Absorption of glucose in the small intestine.
  2. Uptake of magnesium ions in root hair cells of plants.