What Are Lipids? Triglycerides, Phospholipids, and Steroids
Lipids are found in the cell membranes of all living things.
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Transcript
Lipids are an essential part of life. They store energy in our bodies and insulate us from the cold. Some lipids help in transmitting nerve impulses.
Lipids are even found in the cell membranes of all living things.
Lipids are divided into three major classes: triglycerides, phospholipids, and steroids.
Triglycerides are what most people think of when they hear the word lipid. A triglyceride molecule is made up of two parts: a glycerol backbone and three fatty acids.
Glycerol is a small molecule with three hydroxyl groups. A fatty acid is made up of a long hydrocarbon chain and a carboxyl group. When the three hydroxyl groups react with the carboxyl groups, the fatty acids and the glycerol come together to form a triglyceride.
Triglycerides are commonly called fats. They are found in many foods, such as butter, oil, nuts, and meats.
The main function of triglycerides in your body is energy storage. Triglycerides from food are stored in fat cells until it is necessary for your body to break them down for energy.
Phospholipids are complex molecules composed of a phosphate head and two fatty acid tails.
Phospholipids are essential to living organisms because they are a major component in all cell membranes.
They can also be found in foods such as eggs, soy, milk, and some vegetable oils.
Steroids make up a highly diverse group of molecules. Though they may differ in structure, all steroids are made up of four carbon rings. Three of the rings have six carbons, while one ring has just five carbons.
Steroids have many functions within the body. They form the foundation for many hormones, such as testosterone, estrogen, and cortisol, as well as other compounds such as cholesterol and vitamin D.
Lipids are even found in the cell membranes of all living things.
Lipids are divided into three major classes: triglycerides, phospholipids, and steroids.
Triglycerides are what most people think of when they hear the word lipid. A triglyceride molecule is made up of two parts: a glycerol backbone and three fatty acids.
Glycerol is a small molecule with three hydroxyl groups. A fatty acid is made up of a long hydrocarbon chain and a carboxyl group. When the three hydroxyl groups react with the carboxyl groups, the fatty acids and the glycerol come together to form a triglyceride.
Triglycerides are commonly called fats. They are found in many foods, such as butter, oil, nuts, and meats.
The main function of triglycerides in your body is energy storage. Triglycerides from food are stored in fat cells until it is necessary for your body to break them down for energy.
Phospholipids are complex molecules composed of a phosphate head and two fatty acid tails.
Phospholipids are essential to living organisms because they are a major component in all cell membranes.
They can also be found in foods such as eggs, soy, milk, and some vegetable oils.
Steroids make up a highly diverse group of molecules. Though they may differ in structure, all steroids are made up of four carbon rings. Three of the rings have six carbons, while one ring has just five carbons.
Steroids have many functions within the body. They form the foundation for many hormones, such as testosterone, estrogen, and cortisol, as well as other compounds such as cholesterol and vitamin D.