Problem

According to the fluid mosaic model of the plasma…

01:24

Problem 4 Medium Difficulty

How would an organism maintain membrane fluidity in an environment where temperatures fluctuated from very high to very low?
a. Greater proportion of unsaturated phospholipids in membranes.
b. Greater proportion of saturated phospholipids in membranes.
c. Greater proportion of carbohydrates in membranes.
d. Greater proportion of proteins in membranes.

Answer

a

Related Courses

Biology

Biology for AP Courses

Chapter 5

Structure and Function of Plasma Membranes

Discussion

You must be signed in to discuss.

Top Biology Educators

Watch More Solved Questions in Chapter 5

Problem 1

Problem 2

Problem 3

Problem 4

Problem 5

Problem 6

Problem 7

Problem 8

Problem 9

Problem 10

Problem 11

Problem 12

Problem 13

Problem 14

Problem 15

Problem 16

Problem 17

Problem 18

Problem 19

Problem 20

Problem 21

Problem 22

Problem 23

Problem 24

Problem 25

Problem 26

Problem 27

Problem 28

Problem 29

Problem 30

Problem 31

Problem 32

Problem 33

Problem 34

Problem 35

Problem 36

Problem 37

Problem 38

Problem 39

Problem 40

Problem 41

Video Transcript

let's talk a little bit about saturated versus on saturated fatty acids. So, um, a forceful lipid has this general structure over here. It has a phosphate had group and a fatty acid chain, actually to fatty acid chains, usually in a forceful lipid violators. So what does it mean to be saturated and unsaturated so that yellowtail right there What that actually is is a carbon chain. So you can imagine this connects to the next one up. But when we only need to dream, do we only need to draw a couple to make our point here? So it's a carbon chain. It's a carbon connected to requirement connected to a carbon connected to a carbon and not remember that carbon makes four bonds. So the other two bonds for ah carbon is connected to hydrogen, either. Now, what happens in an unsaturated fatty acid? You still have a carbon chain, but instead of single bonds between carbons, you have a double bond, and then the single bonds go this way. So now, because you have a double bond between these two carbons, let's say this carbon at the bottom here it already has to bonds right here it has one bond right here. So that means it only needs one hydrogen to make its four bonds. And same thing for this carbon right here. It has to bonds from this other from this other carbon and has one bond over here. So it needs on Lee one other bond to make four bonds. And this inclusion off this double bond between the two carbons changes the shape of the molecule changes the geometry of how the atoms are arranged with each other. And this is basically what gives rise to this kink right here. That's why that king happens now. Why does this matter? Well, because this kink is there. You see, there's a lot more space between the forceful lipids here between the fatty acid chains. So that means that this lipid right here has a lot more. Movie has a lot more room to move around. Either rotate or translate ah, across the membrane. So this results in more fluid membranes. So oils look more like this, right? The lipids are fluid and they can move around easily on dhe, then saturated Think butter. So when you have a forceful lipids that are saturated that can stack up nicely against each other, and they don't allow each other a lot of room to move. Okay, so now we are being asked, How would a cell that goes from high temperature to look temperature adapt now low temperatures. So let me switch colors here so that we, uh, switch concepts of low temperature leads to slower movement. So if a low temperature is needing is leading to slower movement. That means that it's making the lipid bi layer behaves like as if it had more saturated 50 at of fatty acids. Because that is what happens with violator that has a lot of saturated fatty acids. The fatty acids or the lipids in the bile air, move slowly, and the low temperature has the same effect. So if a, uh cell, if an organism work to compensate for that, it needs to increase the proportion off on saturated lipids to compensate for lower temperature. And that will make the membrane more fluid at lower temperatures. And that is choice eight for our answer here, a greater proportion of unsaturated forceful lipids in membranes, choice bees, greater proportion off saturated lipids. No, that would make things worse. choices, greater proportion of carbohydrates, carbohydrates, sort of sit on the surface of the member. And it don't really affect the lipid membrane that much. In terms of fluidity and choice, these greater proportion of proteins in membranes and choice the, um, also proteins don't really affect the lipid, bi layer of fluidity. That much choice A is our correct answer.

We have video lessons for 96.63% of the questions in this textbook