The answer is e, as in terms of d, proteins are not sandwiched between the two bilayers, but wedged in the bilayer to selectively let in different molecules. With c, phospholipids do not drift, into the membrane, for it is the membrane itself. With b it is the other way around, the phospholipid bilayer makes up the membrane, and proteins are embedded into it. Lastly, for a, a fluid mosaic model wouldn’t portray phospholipids drifting in the dark phospholipid bilayer, as they are an independent molecule consisting only as the cell membrane. Hope that’s helpful! :)
C. When there is an equal number of molecules on each side
Your Achilles tendon was named after the Greek Hero that's only week spot was his tendon ... hope this helped
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Phospholipids are not in the animal cell