Protons are unable to cross the lipid bilayer because a the

Protons are unable to cross the lipid bilayer because:

a) the lipid bilayer is too hydrophilic

b) protons are nonpolar

c) protons are too small

d) the lipid bilayer is only permeable to polar substances

e) none of the above

Solution

Protons are charged ions which are hydrophilic, but the inside of lipid bilayer is hydrophobic so when it try to past the phosphatidyl group it is not permitted by lipid.

speifi transporters are needed for protons entry in lipid bilayer of cell.