https://www.khanacademy.org/science/ap-biology/cell-structure-and-function/membrane-transport/v/introduction-to-passive-and-active-transport 2023-09-14T11:22:40.102153098Z Introduction to passive and active transport Active transport requires energy to move substances against a concentration or electrical gradient, like a canoeist paddling upstream. Passive transport, on the other hand, does not require energy as substances move along their gradient, similar to a canoeist drifting downstream. The sodium-potassium pump is a key example of active transport. Sal Khan video https://cdn.kastatic.org/googleusercontent/fdWO9Yuei6p31qnT761hfXD49OujsJrLlCUkyOZ9fqqBliHjpxCgUmtZzli5EqJlXRbf1Jwzc8Zps-EiJpi5IDvW Introduction to passive and active transport Active transport requires energy to move substances against a concentration or electrical gradient, like a canoeist paddling upstream. Passive transport, on the other hand, does not require energy as substances move along their gradient, similar to a canoeist drifting downstream. The sodium-potassium pump is a key example of active transport. https://cdn.kastatic.org/ka-youtube-converted/TsoAA7zOyj8.mp4/TsoAA7zOyj8.mp4 486 Active transport https://www.khanacademy.org/science/ap-biology/cell-structure-and-function/facilitated-diffusion/a/hs-active-transport-review 2021-04-29T07:49:58Z Active transport review article https://www.khanacademy.org/science/ap-biology/cell-structure-and-function/facilitated-diffusion/a/active-transport 2021-04-29T07:50:55Z Active transport Electrochemical gradients and the membrane potential. Primary and secondary active transport. Na+/K+ pump. article https://www.khanacademy.org/science/ap-biology/cell-structure-and-function/membrane-transport/e/membrane-transport 2025-11-24T20:40:43.982882282Z Membrane transport Test your knowledge of membrane transport! Megan Cohn exercise