Lipids And Fats Essay Research Paper Lipids

Lipids And Fats Essay, Research Paper

Lipids are hydrocarbons that are found in living systems in the environment. The main classes of lipids are triglycerides, waxes, steroids, phospholipids, gylcolipids, and sphingolipids (Glanze). The simplest lipid, which makes up the backbone of all of these, is the fatty acid (see page 2). The main characteristics that separate the different kinds of lipids are the derivatives, such as acids, alcohols, amines, amino alcohols, and aldehydes, found on the end of the hydrocarbons and their solubility in water. Most lipids are nonpolar and there for are not soluble in water but instead in fat solvents such as ether, chloroform, and benzene. From these two basic distinctions, there are dozens of possible lipids that can be formed in nature and synthetically (Cooper).

Triglycerides are compounds consisting of a fatty acid (oleic, palmitic, or stearic) and a glycerol (See page 2). Triglycerides make up most animal and vegetable and are the principal lipids in the blood where they circulate, bound to proteins, forming high- and low-density lipo-proteins; examples of which are lard and butter. This type of lipid is not soluble in water, but is soluble in substances like ether and benzene. Glycerol is an alcohol and is soluble in ethyl alcohol and water. The other main component in is the fatty acid. Fatty acids are any of several organic acids that are unsaturated molecules and cannot be produced by the body. Therefore, fatty acids have to be ingested in an animal s diet (Cooper).

Waxes are fatty esters of long-chain alcohols (See page 3). Theses can be derived from insects, such as beeswax, plants, or petroleum products. There are four main uses for waxes in society. There is a bone wax that is a nontoxic, biocompatible wax used during surgery to plug up cavities in cranial bones and other bones to control bleeding. Because waxes are insoluble in water, they are very useful for the use on humans. Another form of wax is the casting wax with is a mixture of several waxes that can be carved or formed into shapes to be cast in metal. Carnauba wax is used for the general care of cars and used in products like chewing gum. The last use of wax is in dentistry. With the combination of waxes for their specific properties, they can be used in dental procedures (Glanze).

Steroids , or sterol, are a group of substances related to fats. They are alcohols with a cyclic nucleus and are found free or esterified with fatty acids (See page 3). They are found in animals (zoosterols) and in plants (phytosterois). They are generally colorless, crystalline compounds, and soluble in certain organic solvents. The two forms of sterols are cholesterol and ergosterol(Thomas).

The most common steroid is cholesterol. Cholesterol is a fat-soluble crystalline steroid alcohol found in animal fats and oil, and egg yolk, and widely distributed in the body, especially in the bile, blood, brain tissue, liver, kidneys, adrenal glands, and myelin sheaths or nerve fibers(Hole). It helps the absorption and transport of fatty acids and acts as the precursor for the synthesis of vitamin D at the surface of the skin as well as for the synthesis of various other steroid hormones. Among these are cortisol, cortisone, and aldosterone in the adrenal glands and of the sex hormones progesterone, estrogen, and testosterone. Cholesterol is found almost exclusively in foods of animal origin and is continuously synthesized in the body, mainly the liver and the adrenal cortex(Cooper).

Phospholipids are one of a class of compounds, widely found in living cells, containing phosphoric acid, fatty acids, and a nitrogen base (See page 4). The most important kind of phospholipids is lecithin(Marieb). Lecithin is a lipid most common in animals and plants. Lecithins are found in the liver, nerve tissue, semen, and in smaller amounts in bile and blood. They are essential for the metabolism is fats and are used in the processing of foods, pharmaceutical products, cosmetics, and inks. Rich sources of these are found in soybeans, egg yolks, and corn(Glanze).

Glycolipids are compounds that consists of a lipid and a carbohydrate, usually galactose, found primarily in the tissue of the nervous system, especially the myelin sheath and the ganglion cells (See page 3). The most important of these lipids are the cerebrosides. The glycolipids are found in the brain and other tissue of the nervous system, especially the myelin sheath(Thomas).

Sphingolipids are compounds that consist of a lipid and a sphingosine (See page 4). It is found in high concentrations in the brain and other tissues of the nervous system, especially membranes. The most important of these lipids is the sphingomyelin. This is a group of lipids containing phosphorus. It occurs primarily in the tissue of the nervous system, generally in membranes, and in the lipids in the blood. Another type of sphingolipid is cerebroside, which is also a glycolipid(Cooper).

In the body, fats are the most concentrated source of energy(Marieb). They contain very little water, and the energy given off form the catabolism of fats is approximately twice that gained form either glucose (the most simple sugar) or protein breakdown. The primary fat is triglyceride, an ester of three fatty acids and a glycerol. This substance is not digested in the stomach and passes into the duodenum (the first part of