00:01
We're looking at the lipid bilayer, which of these would be the least fluid? so, phospholipids with 18 carbon atoms, two double bonds, fully saturated 18, fully saturated 20, or 20 with two double bonds.
00:16
Okay, so we have two factors to look at here, length of tail and saturation of tail, which would be most and least fluid.
00:25
So fluidity is kind of a measure of the ability of the phospholibis to move around.
00:30
And they will be less fluid if they are either lower temperature or if they are interacting more.
00:37
So more interactions between the tails means less fluid.
00:47
And there are interactions between the tails.
00:49
They might not form hydrogen bonds like water does, but they interact, they have band of our forces.
00:55
So more interactions, the first thing this means is longer tails.
01:01
Longer tails means less fluidity, because longer tails have more molecules in them, more atoms in them, i mean, and that means they get more interactions.
01:11
So if we're looking for the least fluid, we can roll out the shorter tails, and just focus on the longer ones...