CELL STRUCTURES AND FUNCTION
BIO MOLECULES
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[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Detailed explanation-1: -All steroids are related to a characteristic molecular structure composed of 17 carbon atoms-arranged in four rings conventionally denoted by the letters A, B, C, and D-bonded to 28 hydrogen atoms.
Detailed explanation-2: -All steroids have a characteristic structural component consisting of four fused rings. Chemists identify the rings by capital letters and number the carbon atoms as shown in Figure 17.4.
Detailed explanation-3: -Four fused hydrocarbon rings comprise steroids such as cholesterol and cortisol. Cholesterol is the most common steroid. The liver synthesizes cholesterol and is the precursor to many steroid hormones such as testosterone and estradiol, which gonads and endocrine glands secrete. It is also the precursor to Vitamin D.
Detailed explanation-4: -The steroid core structure is typically composed of seventeen carbon atoms, bonded in four “fused” rings: three six-member cyclohexane rings (rings A, B and C in the first illustration) and one five-member cyclopentane ring (the D ring).