Carbohydrates

1
Carbohydrates

• The Chemistry of Life
• (Biochemistry)

2
Carbohydrates fuel and building material

• Exist as three types
• 1. monosaccharides
• 2. disaccharides
• 3. polysaccharides (macromolecule stage)
• Made up of C, H, and O
• Has carbonyl group and multiple hydroxyl groups
  (location of carbonyl determines if is an aldose
  or a ketose
• Names end in ose
• Size of carbon skeleton determines category

3
Monosaccharides

• Are major sources of energy for cells
• Ex. Glucose cellular respiration
• Are simple enough to serve as raw materials for
  synthesis of other small organic molecules such
  as amino and fatty acids
• Most common glucose, fructose, galactose

4
Figure 5.3 The structure and classification of
some monosaccharides
5
Glucose, Fructose, Galactose

• Glucose made during photosynthesis
• main source of energy for plants and
  animals
• Fructose found naturally in fruits
• is the sweetest of monosacc
• Galactose found in milk
• is usually in association with glucose
  or fructose

6
Diaccharide

• Disaccharide two monosaccharide bonded together
  with the release of water. Exp. Table sugar, and
  lactose (sugar in milk) these must be broken down
  by the enzymes in our stomach to be utilized by
  the body

7
Figure 5.5 Examples of disaccharide synthesis
8
Polysaccharide

• Polysaccharide many monomers bonded together
  (12 or more) complex carbohydrate the best type
  to eat. Pasta is a polysaccharide, Plant
  starches also contain fiber, which is good for
  you digestion, and it cant be broken down in our
  bodies and just passes thought to help cleanse
  the colon.

9
Figure 5.7b,c Starch and cellulose structures 
10
Chemical Identification of Carbohydrates

• Benedicts Test Identifies the presence of a
  MONOSACCHARIDE by changing from blue to orange in
  the presence of heat
• Iodine Test Identifies the presence of a
  POLYSACCHARIDE by changing from yellow to
  purple/black
• Process of Elimination If there is no reaction
  with either the Benedicts or Iodine Tests, then
  a DISACCHARIDE is present.