Chapter 15 Carbohydrates 15 1 Carbohydrates General Organic

Carbohydrates are § a major source of energy from our diet § composed of the elements C, H and O § also called saccharides, which means “sugars” General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 2

Carbohydrates (continued) Carbohydrates § are produced by photosynthesis in plants § such as glucose are synthesized in plants from CO 2, H 2 O, and energy from the sun § are oxidized in living cells (respiration) to produce CO 2, H 2 O, and energy General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 3

Types of Carbohydrates The types of carbohydrates are § monosaccharides, the simplest carbohydrates § disaccharides, which consist of two monosaccharides § polysaccharides, which contain many monosaccharides General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 4

Monosaccharides consist of § 3 to 6 carbon atoms (typically) § a carbonyl group (aldehyde or ketone) § several hydroxyl groups General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 5

Naming Monosaccharides Names of monosaccharides § end in -ose § may include the number of carbons in the molecule: triose (3 C atoms) tetrose (4 C atoms) pentose (5 C atoms) hexose (6 C atoms) General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 6

Aldoses are monosaccharides § with an aldehyde group § with many hydroxyl (—OH) groups § Examples: aldotriose (3 C atoms) aldotetrose (4 C atoms) aldopentose (5 C atoms) aldohexose (6 C atoms) General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 7

Ketoses are monosaccharides § with a ketone group § with many hydroxyl (—OH) groups § Examples: ketotriose (3 C atoms) ketotetrose (4 C atoms) ketopentose (5 C atoms) ketohexose (6 C atoms) General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 8