Answer:
Lactose
Lactose is a disaccharide found in milk. It consists of a
molecule of D-galactose
and a molecule of D-glucose
bonded by beta-1-4 glycosidic
linkage. It has a formula of C12H22O11.
A carbohydrate is an organic compound with the
empirical formula Cm(H2O)n (where m could be
different from n); that is, consists only of carbon, hydrogen, and oxygen, with a
hydrogen:oxygen atom
ratio of 2:1 (as in water).
However, there are exceptions to this. One common example would be deoxyribose, a component
of DNA, which has the empirical formula C5H10O4.
Carbohydrates can be viewed as hydrates
of carbon, hence their name. Structurally however, it is more accurate to view
them as polyhydroxy
aldehydes and ketones.
The term is most common in biochemistry, where it is
a synonym of saccharide. The carbohydrates (saccharides) are divided
into four chemical groupings: monosaccharides, disaccharides, oligosaccharides, and polysaccharides. In
general, the monosaccharides and disaccharides, which are smaller (lower molecular weight)
carbohydrates, are commonly referred to assugars. While the
scientific nomenclature of carbohydrates is complex, the names of the
monosaccharides and disaccharides very often end in the suffix -ose. For example, blood sugar is the
monosaccharide glucose,
table sugar is the disaccharide sucrose,
and milk sugar is the disaccharide lactose
Carbohydrates perform numerous
roles in living things. Polysaccharides serve for the storage of energy (e.g., starch and glycogen), and as
structural components (e.g., cellulose
in plants and chitin
in arthropods). The 5-carbon monosaccharide ribose is an important
component of coenzymes
(e.g., ATP,
FAD, and NAD)
and the backbone of the genetic molecule known as RNA. The related deoxyribose is a component
of DNA. Saccharides and their
derivatives include many other important biomolecules that play key
roles in the immune system, fertilization, preventing pathogenesis, blood clotting, and development.
In food science and in many
informal contexts, the term carbohydrate often means any food that is particularly
rich in the complex carbohydrate starch
(such as cereals, bread, andpasta) or simple
carbohydrates, such as sugar
(found in candy, jams, and desserts).
Assignment submitted by L.Y., Kong, S. H., Lim, S. C., Soo, C. W. Tan and C.C.,Teh 2011/2012 (IBM)
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