Triglycerides (neutral fats)- This group is known as the fats. Triglycerides are composed of one molecule of glycerol and joined via ester bonds with 3 molecules of fatty acids. Fatty acids are long chains of carbon (C) and hydrogen (H) usually between 14-24 carbons long. Due to the abundance of the carbon and hydrogen, fatty acids are very hydrophobic and are not very soluable in water. Fatty acids come in two major types, saturated and unsaturated. Saturated means they are “completely saturated” with hydrogen and have no double bonds. Unsaturated means that they are not saturated with hydrogen and it contains double bonds. Saturated fats have a high melting point so they are solid at room temperature. Saturated fats are found in animals. Unsaturated fats have a lower melting point and are a liquid at room temperature. Unsaturated fats are found in plants. The primary cellular function of fatty acid is as long term energy storage. The body will store a small amount of excess nutrients as glycogen, after a certain point, these nutrients are converted to triglycerides for storage. Triglycerides are efficient energy storing molecules as more energy can be stored in a pound of fat rather than a pound of glycogen.
Steroids- This class of lipids does not have anything in common with triglycerides other than them both being hydrophobic. All steroids are derivatives of a common structure made up of four fused carbon rings. Each steroid contains different chemical groups attached to those rings. The most common steroid is cholesterol.
Phospholipids- This class of lipids are really derivatives of triglycerides. They are composed of a glycerol molecule with two fatty acids. The third carbon contains a phosphate group and usually polar molecule. Much of the molecule is hydrophilic just like triglycerides. The phosphate is highly charged this part is hydrophilic. Any molecule that is hydrophobic at one end and hydrophobic at another is said to be amphipathic.
Lipids are important to the body because they produce energy and provide a place to store energy, they also produce hormones. Without lipids we wouldn’t be able to digest and absorb food properly. The primary role of lipids is to provide energy for muscles and body processes. Lipids are also used to insulate and protect your body. The essential lipids are vital to our health and they cannot be made in our bodies they must come from our diets. They are used in the production of cell membranes and hormones as well as maintaining vision and supporting the immune system. Omega-3 and Omega-6 have many health benefits. Omega-3 is an essential fatty acid that plays a role in brain function and can help you fight cardiovascular disease. Omega-6 combined with omega-3 produces many of the health benefits as omega-3. Omega- 3 and Omega-6 benefits our health by supporting asthma, diabetes, high cholesterol, arthritis, osteoporosis, some cancers, skin disorders, high blood pressure, attention disorders, depressive disorders, digestive difficulties, and macular degeneration. Lipids cannot cross the plasma membrane on their own the transportation of these vital substances is carried out by certain classes of intrinsic proteins that form a variety of transport systems. Open channels allow ions to diffuse directly into the cell; others are “facilitators,” which, through a little-understood chemical transformation, others are “pumps,” which force solutes through the membrane when they are not concentrated enough to diffuse spontaneously. Particles too large to be diffused or pumped are often swallowed by an opening and closing of the membrane.
Cholesterol is a waxy, fat-like substance that’s found in all cells of the body. Our body makes all the cholesterol it needs. However, cholesterol…