Lipids

[Music] hi it's Mr Anderson and in this podcast I'm going to talk about lipids or the fats the fat that's found in butter or the fat that's found in olive oil is what we call a triglyceride it's basically going to have a head a glycerol head and then it's going to have three fatty acid tails and that's where the energy is and so when we eat fat we can break it down we have enzymes called light bases that are able to break that down and then we can get energy from it and that's been very

important we can store energy and fats inside our body and then we can burn them when we need them but don't forget that fats in addition to providing energy also provide the surroundings and so the cell membrane that goes around every cell is made up of phospholipids and the cholesterol is found within the phospholipid bilayer and that maintains the fluidity of the cell and so lipids are incredibly important but where does the energy come from that comes from the hydrocarbons and so if you look at those fatty acid tails it's essentially a carbon attached to

a carbon to a carbon to a carbon to carbon to carbon to carbon to carbon to carbon to carbon to carbon to carbon to carbon carbon carbon carb carbon carbon carb carb carb car carb and then it has hydrogen around the outside of it and so we call that a hydrocarbon and there's energy in those bonds and so gasoline burning out of control or the paraffin wax that's burning in a candle is a hydrocarbon there's a lot of energy between those carbon hydrogen bonds and so there's also a lot of energy found in butter or

in olive oil it's in the bonds between the carbon and the hydrogen and so let's start with the triglyceride so this is a basic fat the head up here is going to be called the glycerol head and then this is going to be the fatty acid tails that go down the end and so a fatty acid tail has so much carbon and hydrogen in it that on this diagram we don't even draw them each of these points represents a carbon a carbon a carbon and then right here we're going to have two hydrogen bonds uh

or two hydrogens bonded to each of those carbon and so you can see that there's a huge amount of energy locked within that triglyceride and we can get that out through cellular respiration but know this those Tails can come in two different forms we can have what are called saturated Tails a saturated tail is going to have hydrogen all the way around the outside and if you have hydrogen all the way around the outside then you're going to be saturated with hydrogen and if you're a saturated fat you're going to be a straight fat and

so a triglyceride is going to have three of these fatty acet Tales and The glycerol head but if it is saturated all of those are going to be straight and if they're all straight they can pack up on top of other triglycerides and so saturated fats are normally going to be a solid at room temperature what happens if you don't have hydrogen all the way around the outside you're going to form these double Bonds in here if you have double bonds basically what that does is puts a bend in your tail and so you're going

to have a kinky tail and so if you're a Satur saturated fat you're going to look like this if you're an unsaturated fat you're going to look like this with kinky tails and the kinky Tails can't quite pack together and so normally fats that are unsaturated are going to be a liquid at room temperature now humans have figured out how to take for example vegetable oil which is a um unsaturated fat or it's going to be a liquid at room temperature and we can bubble hydrogen through it we can straighten out those tails and we

can make a saturated fat called margarine that's going to be a solid at room temperature we've transformed this fat and if you know anything about fats those saturated fats are the ones that are least best for us and can lead to arterial sclerosis especially trans fats example then of of how we've tried to get around this and this is somewhat funny story this is alestra alestra is a fat that was made by humans and so basically what they did is took a normal triglyceride but they built it around a sucrose so they built it around

a sugar and so instead instead of having just three of these fatty acid Tails they had sometimes eight sometimes 10 sometimes even more what's neat about that is that when you go through your digestive system we don't have olr we don't have an enzyme that can break that down and so the oestra moves right through our digestive system so it's a fat that feels like a fat tastes like a fat but it doesn't make us fat and so WOW chips were introduced I think in the 19s 1990s and had this alestra in it and uh

basically what happened is when people started eating these wild chips they got incredibly sick they got cramping and they had to put a warning label on the outside that can lead to loose stools and it pulls vitamins outside of your body they've kind of refined this since uh since since then and so there's not a lot of these adverse reactions uh I think Pringles like light chips still contain olestra in it but we're tricking our body because the body doesn't have those enzymes now I also said there are two more important lipids first one's called

phospholipids phospholipids are going to have you can see two fatty acid Tails but they're going to have a head that contains a phosphate group that phosphate group is going to have a negative charge and so normally if we were to pour oil into water it's going to separate and the reason why is that fats are non-polar they don't have a charge but what's neat about phospholipids is that they have a head that is going to have a negative charge and then they have the tails that are uncharged and so if you just throw a bunch

of phospholipids in water they'll form these spheres these my cells or they'll form these spontaneous membranes and so the cell membranes of all cells are made up of phospholipids and so bacteria ARA ukaria plants animals fungi we all have cell membranes and those membranes are made up of phospholipids they regulate what gets in and out of a cell cholesterol is going to maintain the fluidity of the membrane and so this cell membrane right here is made up of phospholipids those fosil lipids are constantly moving back and forth and that's important because it allows things like

oxygen to get in and carbon dioxide to get out but if the cell gets heated up those phospholipids tend to fall apart and if it gets really cold they'll crowd together and so the function of cholesterol is to grab onto those fatty acid tails and hold them together when it gets too cold but keep them apart uh or hold them together when they get too warm and keep them apart when they get too cold and so cholesterol is important at maintaining that Integrity of the cell membrane and you can see cholesterol in this diagram right

here um we can build it in each of our cells and we have to build it in our cells but we have to get a little bit of it in our diet and so we need lipids in our diet if we don't have lipids we can't get energy and more importantly we can't make our cell membranes however today everybody's getting the fat that they need this is my favorite place to eat when I go to California because we don't have them in Montana this is In-N-Out Burger I love the taste of a big burger from

in and out um the lipids are great but there's probably too much trans fats in there it's not good for me and could lead to hard disease but for now I'm going to keep eating them so that's lipids that's fat and I hope that was helpful