Many Forms of Lipids

Lipids are another type of organic molecule. Remember that organic means they contain carbon (C) atoms. It's not like organic farming at all. When you think of fats, you should know that they are lipids. Lipids are also used to make steroids and waxes. So, if you pick out some earwax and smell it, that's a lipid, too!

Get the Wax Out of Your Ears

Waxes are used to coat and protect things in nature. Bees make wax. It can be used for structures, such as the bees' honeycombs. Your ears make wax. It is used to protect the inside of your ear. Plants use wax to stop evaporation of water from their leaves. There is a compound called cutin that you can find in the plant cuticle covering the surface of leaves. It helps to seal and protect plant structures. Don't worry about plants being able to breathe. There are still small holes that let gases in and out of the leaves.


Steroid Molecules Steroids are found in animals within something called hormones. The basis of a steroid molecule is a four-ring structure: one ring with five carbons and three rings with six carbons. You may have heard of steroids in the news. Many bodybuilders and athletes have used anabolic steroids to build muscle mass. The steroids make their bodies add more muscle than they would normally be able to. Those anabolic steroids help bodybuilders wind up stronger and bulkier (but not faster). Steroids are also used in necessary medicines. Some help people with acne, while others are used as muscle relaxers for injuries.

NOTE: Never take drugs to enhance your body. Those athletes are actually hurting their bodies. They can't see it, because it is slowly destroying their internal organs and not the muscles. When they get older, they can have kidney and liver problems. Some even die.


Glycerol molecules Fat is also known as a triglyceride. It is made up of a molecule known as glycerol that is connected to one, two, or three fatty acids. Glycerol is the basis of all fats and is made up of a three-carbon chain that connects the fatty acids together. A fatty acid is just a long chain of carbon atoms connected to each other.

Saturated and Unsaturated

There are two kinds of fats, saturated and unsaturated. Unsaturated fats have at least one double bond in one of the fatty acids. A double bond happens when four electrons are shared or exchanged in a bond. They are much stronger than single bonds with only two electrons. Saturated fats have no double bonds.

Fats have a lot of energy stored up in their molecular bonds. That's why the human body stores fat as an energy source. When you have extra sugars in your system, your body converts them into fats. When it needs extra fuel, your body breaks down the fat and uses the energy. Where one molecule of sugar only gives a small amount of energy, a fat molecule gives off many times more.

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