Active Transport

• Active transport is the movement of particles against a concentration gradient (from low to high concentration) through proteins using some of the energy from respiration.
• Active transport requires energy so it is an active process.
• In humans, active transport allows sugar molecules to be absorbed from the small intestine when the sugar concentration is higher in the blood than in the small intestine.
• In plants, active transport is used to absorb mineral ions into the root hair cells from more dilute solutions in the soil.
• The minerals a plant requires are nitrates, phosphates and potassium compounds.
• Nitrates are formed from nitrogen which is needed to make amino acids for proteins. Proteins are needed for cell growth.
• Phosphates are formed from phosphorus and are needed to make DNA and call membranes.
• Potassium compounds are formed from potassium and are needed in the enzymes involved in respiration and photosynthesis.
• Active transport moves substances from a more dilute solution to a more concentrated solution (against a concentration gradient). This requires energy from respiration.
• Active transport allows mineral ions to be absorbed into plant root hairs from very dilute solutions in the soil. Plants require ions for healthy growth.
• Active transport allows sugar molecules to be absorbed from lower concentrations in the gut into the blood which has a higher sugar concentration. Sugar molecules are used for cell respiration.