Answer:
The two main reasons are nonpolar core of the bilayer and the active transport.
Explanation:
The membrane is structured to have two outer layers that are polar and an inner layer that is nonpolar. 
If a membrane protein is exposed to the solvent, i<em>t will also have a polar side. It would be very difficult for the polar face of the membrane to move through the nonpolar core of the bilayer.</em> Therefore, this model is not feasible.
One major form of transport, active transport, moves solutes up the concentration gradient. <em>The binding of a solute and then release on another side of the membrane would only work for facilitated diffusion because it would cause a net movement of solutes down the concentration gradient.</em> It is unclear how energy could be expended to drive this process in the transverse carrier model.<em> Therefore, the transverse carrier model does not explain active transport.</em>
 
        
             
        
        
        
Answer:
the one with the race horse. brainliest?
Explanation:
 
        
             
        
        
        
<span>a.) oyster   
hope it helped
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