In EK Bio 1001 #241 they are saying that at high temperature you would have the lowest ratio of unsat to sat fatty acids (FA's). At high temp, the cell is trying to keep the membrane from becoming TOO fluid. So the relative amount of saturated FA's would increase. This would make the unsat/sat ratio LOW. UNSAT:SAT = LO:HI.
Conversely, in cold temperature the membrane wants to INCREASE fluidity. It will do this by introducing, among other things, a larger proportion of unsaturated FA's.
Sat FA's = less fluid because they pack very well
Unsat FA's = more fluid because they don't pack as well (they're "kinky")
So at lo temp: unsat FA: sat FA ratio is HIGH.
They are saying in the key that unsaturated: saturated FA ratio will be LOWEST at lower temp. I am arguing the opposite. At low temp, when you want to increase fluidity, why would you introduce saturated FA's?? it's the exact opposite of what the body does.
(of course, the membrane also regulates fluidity via cholesterol and FA chain length... and probably other methods also).
Conversely, in cold temperature the membrane wants to INCREASE fluidity. It will do this by introducing, among other things, a larger proportion of unsaturated FA's.
Sat FA's = less fluid because they pack very well
Unsat FA's = more fluid because they don't pack as well (they're "kinky")
So at lo temp: unsat FA: sat FA ratio is HIGH.
They are saying in the key that unsaturated: saturated FA ratio will be LOWEST at lower temp. I am arguing the opposite. At low temp, when you want to increase fluidity, why would you introduce saturated FA's?? it's the exact opposite of what the body does.
(of course, the membrane also regulates fluidity via cholesterol and FA chain length... and probably other methods also).
