The external and internal environment of the cell is basically water, thus phospholipids organize themselves the way they do (bilayer). If the environment were to magically become mostly heptane, how would the phospholipid orientation change?

Phospholipids maintain their structure in the cell membrane because of the hydrophilic heads and the hydrophobic tails. Much unlike water, Heptane (CH3-CH2-CH2-CH2-CH2-CH2-CH3) is non polar and thus would not cause the heads to present themselves on the outer bilayer and the tails to tuck themselves away.

Because heptane is non polar, I wouldn't expect there to by any hydrogen-bonding going on, so I don't think that we would see an "inverted bilayer". I could be wrong though.

My thought - the cell membrane would cease to exist, I can't think of what would hold it together, but that seems a bit out there. Thoughts?

  • $\begingroup$ Is this a homework question? If so note that the SE Biology policy on homework questions indicates it should be tagged as such. $\endgroup$ – David Oct 11 '18 at 22:19
  • $\begingroup$ Yes, this is a homework question. I'll go ahead and tag. Also not really looking for an outright answer, more just guidance on my current train of thought. Which... do you have any? Also, I feel like I've met all the rules. biology.stackexchange.com/help/homework $\endgroup$ – Podo Oct 11 '18 at 22:23
  • 3
    $\begingroup$ I agree that you have followed the rules. Your answer that the membrane would cease to exist seems most reasonable to me, but I suppose you are expected to think about the polar and non-polar parts of the phospholipid and which would orient itself to the hydrophobic heptane. I hate this sort of question, because this only works if you assume that the membrane is still surrounding a cell with an aqueous interior and the membrane still exists. I assume your instructor knows this is so, but you or I would not, which is not fair on you (I don't care). $\endgroup$ – David Oct 11 '18 at 22:41

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.