Steroids Contain Four Carbon Rings

TABLE 13.1 DEGREE OF UNSATURATION IN SOME COMMON FATS 

Was this your answer They are both lipids and, hence, insoluble in water. 

The general structure of an amino acid, with R representing the side group that makes each amino acid different from all others. 

The sex hormones estradiol and tesiostenone are steroids that the body produces from the most abundant steroid of all—cholesterol. 

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All steroids contain a tetracyclic ring system. The four rings are designated A, B, C, and D. A, B, and C are six-membered rings and D is a five-membered ring. The carbons in the steroid ring system are numbered as shown. 

Steroids are molecules that contain four fused rings—three rings with six carbons in them, and one ring with five carbons. As a class of compounds, steroids include cholesterol and certain hormones. 

Steroids lipids that contain four fused carbon rings, three containing six carbons and one containing five carbons, include cholesterol and the sex hormones Sterols see Steroids... 

Terpenes are natural products usually obtained from the essential oils of plants. They contain multiples of five-carbon atoms (5, 10, 15, and so on). Each five-carbon arrangement is called an isoprene unit, a four-carbon chain with a one-carbon branch at C-2. Terpenes are frequently used in fragrances and perfumes. Steroids are lipids that contain a unique four-ring structure and are biosynthetically related to terpenes. Important examples of steroids include cholesterol, the bile acids, and the sex hormones. 

All steroids contain the basic structures in Figure 6.11. Steroids are fat-soluble lipids. Their structures are based on the tetracyclic (four rings) structure shown in Figure 6.11. Three of the rings have six carbons in them, whereas the other have five... 

Within the lipid family, there are specific structures that distinguish the different types of lipids. Lipids such as waxes, fats, oils, and phospholipids are esters that can be hydrolyzed to give fatty acids along with other molecules. Steroids are characterized by the steroid nucleus of four fused carbon rings. They do not contain fatty acids and cannot be hydrolyzed. Figure 15.1 illustrates the types and general structure of Upids we will discuss in this chapter. 

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