Active Transport

• Active transport requires ATP hydrolysis and moves substances against their concentration gradients.
• Active transport involves the roles of carrier proteins and the importance of the hydrolysis of ATP.
• 𝙄𝙈𝙋𝙊𝙍𝙏𝘼𝙉𝘾𝙀 𝙊𝙁 𝘼𝘾𝙏𝙄𝙑𝙀 𝙏𝙍𝘼𝙉𝙎𝙋𝙊𝙍𝙏:

  • reabsorption of useful molecules and ions into the blood after filtration into kidney tubules

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  • absorption of some products of digestion from the digestive tract.​

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  • loading sugar from the photosynthesising cells of leaves into the phloem tissue for transport around the plant.​

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  • loading inorganic ions from the soil into root hairs.
• Sodium ions are actively transported out of epithelial cells by the sodium-potassium pump into the blood. This takes place in one type of protein-carrier molecule found in the cell-surface membrane of the epithelial cells.

  This maintains a much higher concentration of sodium ions in the lumen of the intestine than inside the epithelial cells.