The movement of materials across the cell membrane without using cellular energy is called passive transport. The movement of materials against a concentration difference is known as active transport. Active transport requires energy.
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passive
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Active transport requires energy; passive transport does not.
passive
Active transportation and passive transportation (found in facilitated diffusion and osmosis)
active components can have gain, passive can't.
active
active transportation is the movement of molecules from a less crowded area to a more crowded area. passive transportation is the movement of molecules from a more crowded area to a less crowned area.
Active - Active Active - Passive
The two different types of sonar are passive and active.
passive
Active transport requires energy because you are going against a gradient. Active transportation moving from low to high concentration, while passive transportation such as osmosis and diffusion go from high to low concentration. One example of passive transportation is a river. Floating downstream does not require any energy. You are simply moving with the gradient. If you wanted to go upstream, you would have to paddle. This requires an input of energy similar to active transport.
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active and passive
== == "English grammer active and passive voice change from active to passive .
Passive