THE CELL
CELL THEORY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Molecules like glucose are large and need to get into cells quickly, so they enter the cell using protein channels which requires energy in the form of ATP.
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Molecules like oxygen are very large and need to get into the cell quickly and must use protein channels to enter the cell.
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All particles going through protein channels require energy in the form of ATP.
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When protein channels do not allow particles to reach equilibrium it requires energy in the form of ATP.
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Detailed explanation-1: -Sometimes molecules need the help of special transport proteins to move across the cell membranes. The movement of molecules across a membrane without the input of energy is known as passive transport. When energy (ATP) is needed, the movement is knownAs active transport.
Detailed explanation-2: -All channel proteins and many carrier proteins allow solutes to cross the membrane only passively (“downhill”), a process called passive transport, or facilitated diffusion.
Detailed explanation-3: -The plasma membranes of many cells also contain water channel proteins (aquaporins), through which water molecules are able to cross the membrane much more rapidly than they can diffuse through the phospholipid bilayer.
Detailed explanation-4: -Channel proteins span the membrane and make hydrophilic tunnels across it, allowing their target molecules to pass through by diffusion. Channels are very selective and will accept only one type of molecule (or a few closely related molecules) for transport.