Quick question on Lipid bilayer

[csx]

the portion that is facing the cellular interior....is it hydrophilic or h.phobic? I said phobic but apparently i am wrong and that is confusing me... I thought the exterior and interior is phobic with the philic parts of the lipids sandwiched inbetween.

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[Cawolf]

It is the reverse of what you said.

The "heads" are facing the cytosol and extracellular fluid - they are polar phosphate groups (phillic).

The "tails" are "sandwiched" in between the "heads" - they are non polar lipid chains (phobic).

 

[csx]

It is the reverse of what you said.

The "heads" are facing the cytosol and extracellular fluid - they are polar phosphate groups (phillic).

The "tails" are "sandwiched" in between the "heads" - they are non polar lipid chains (phobic).

omy jesus, wth is wrong with me.

That said, I thought the lipid bilayer is hydrophobic on the exterior which allow steroids to diffuse through. Wouldn't they be unable if the hydrophilic parts are on the exterior?

 

[Cawolf]

Lipids pass through because they are non-polar and are not repelled by the phosphate groups.