Which Is True About Mediated Transport Across Cell Membranes

question 59

Multiple Choice

Which is true about mediated transport across cell membranes?

• A)It refers to the movement of ions through protein channels.
• B)It refers both to simple diffusion and to the active transport of molecules.
• C)It is characterized by saturable carriers and a maximum velocity of transport.
• D)As the concentration gradient across a membrane increases,the transport rate always increases.
• E)It is nonspecific;any transporter can transport any molecule across the cell membrane.

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Definitions:

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