Respuesta :

Navy2017
 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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