Respuesta :
some small polar molecules are capable of permeating the lipid bilayer without the aid of a membrane transport protein. Examples include water ,glycerol ,urea, and ethanol.
Answer:
Only small, nonpolar substances can pass directly through the phospholipid bilayer.
Explanation:
Other substances that need to pass through the phospholipid bilayer for maintaining homeostasis will make use of membrane proteins.
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