Active Transport

• What is the definition of active transport? 


  The movement of molecules across a membrane , from a region of lower concentration to a region of higher concentration- requires energy from respiration (in form of ATP)
• What does ‘against the concentration gradient’ mean?


  Movement from lower concentration to higher concentration
• How do plant root hair cells use active transport?


  To absorb mineral ions (such as magnesium and nitrate ions) and water from the soil.
• Does active transport require energy?


  Yes
• Which sub-cellular structure (organelle) provides the energy required for active transport?


  Mitochondria
• How are diffusion and active transport involved in the process of glucose being absorbed into the bloodstream from the gut in humans?


  • At first glucosed in absorbed by diffusion because there is a higher concentration in the small intestine than in the bloodstream
  • However once most of the glucose has been absorbed there will be a higher concentration in the bloodstream and so the remaining glucose will have to be absorbed by active transport