Describe the chemical structures of the dietary carbohydrate family
What will be an ideal response?
The dietary carbohydrate family includes:
Monosaccharides: Single sugars
Disaccharides: Sugars composed of pairs of monosaccharides
Polysaccharides: Large molecules composed of chains of monosaccharides
Monosaccharides and disaccharides (the sugars) are sometimes called simple carbohydrates, and polysaccharides (starches and fibers) are sometimes called complex carbohydrates.
Glucose, fructose, and galactose are the three monosaccharides most important in nutrition and all have the same numbers and kinds of atoms. Each contains six carbon atoms, 12 hydrogens, and six oxygens (written in shorthand as C6H12O6), but differ in the arrangement of the atoms. These chemical differences account for the differing sweetness of the monosaccharides.
The disaccharides are pairs of the three monosaccharides just described. Maltose is composed of two glucose units. Sucrose is composed of one glucose unit and one sucrose unit. Lactose is composed of one glucose unit and one galactose unit. These carbohydrates—and all the other energy nutrients—are put together and taken apart by similar chemical reactions: Condensation and hydrolysis.
In contrast to the aforementioned simple carbohydrates just mentioned, the polysaccharides are slightly more complex, containing many glucose units and, in some cases, a few other monosaccharides strung together. Three types of polysaccharides are important in nutrition: Glycogen, starches, and fibers. Glycogen is a storage form of energy in the body; starch is the storage form of energy in plants; and fibers provide structure in stems, trunks, roots, leaves, and skins of plants. Both glycogen and starch are built of glucose units; fibers are composed of a variety of monosaccharides and other carbohydrate derivatives.
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A. a loss of vitamins. B. a loss of oils. C. a loss of fiber. D. a loss of protein.
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a. depression or social isolation b. recent unintentional weight change c. history of chronic illness d. age