SCIENCE
CELL BIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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up the concentration gradient
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from an area of lower concentration to an area of higher concentration
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in a direction that doesn’t depend on concentration
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down the concentration gradient
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Detailed explanation-1: -In facilitated diffusion, molecules diffuse across the plasma membrane with assistance from membrane proteins, such as channels and carriers. A concentration gradient exists for these molecules, so they have the potential to diffuse into (or out of) the cell by moving down it.
Detailed explanation-2: -In simple diffusion, small noncharged molecules or lipid soluble molecules pass between the phospholipids to enter or leave the cell, moving from areas of high concentration to areas of low concentration (they move down their concentration gradient).
Detailed explanation-3: -The rate of diffusion is directly proportional to the concentration gradient. Higher the concentration gradient, the faster the rate of diffusion.