THE CELL
TRANSPORT INTO AND OUT OF THE CELL
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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semi-permeable
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permeable
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diffusion
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concentration gradient
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Detailed explanation-1: -A membrane which allows certain substances to pass through it, but not others is called a selectively permeable membrane.
Detailed explanation-2: -Cell membranes are an example of semi-permeable membranes. Cell membranes allow small molecules such as oxygen, water carbon dioxide and glucose to pass through, but do not allow larger molecules like sucrose, proteins and starch to enter the cell directly.
Detailed explanation-3: -The semi-permeable nature of cell membranes allows cells to exchange nutrients and wastes with the blood while otherwise maintaining control over their own contents. Whether a given molecule can get through a cell membrane depends on such factors as the size and polarity of the molecule.
Detailed explanation-4: -Other types of semipermeable membranes are cation-exchange membranes (CEMs), anion-exchange membranes (AEMs), alkali anion exchange membranes (AAEMs) and proton-exchange membranes (PEMs).