Carbohydrates
10/13/09
II. Organic Compounds
1. Carbohydrates – contain C, H, O in a ratio of 2H to
1 O.
a. Monosaccharides – simple sugars.
ratio of C to H to O is 1 to 2 to 1. (C6H12O6).
Ex. Glucose , fructose, galactose
(us)
(fruits) (milk)
* all 3 have same chemical formula but differ in their
structural arrangement – called isomers
Same chemical formula C6H12O6, different structural arrangement
Galactose
Glucose
Fructose
B. Disaccharides – combining of 2 monosaccharides
through a condensation reaction
ex. Sucrose (sugar,beets) – made of fructose
and glucose.
lactose(milk) – made of glucose and
galactose.
C. Polysaccharide – 3 or more monosaccharides
Ex. glycogen (stored animal sugar), starch
(stored plant sugar), cellulose (plant cell wall),
chitin (exoskeleton in arthropods)
**Characteristics of Carbon**
Carbon-13 and Carbon-14 isotopes (difference in
neutrons) can be used for radioactive
isotopes.
Carbon can form four bonds (CH4, C2H6), which
allows carbon to form stable and strong
covalent bonds.
**Characteristics of Carbon**
• Carbon can also form three different shapes:
ringed, branched or straight.
HHHHHH
H C-C-C-C-C-C H
HHHHHH
Straight
Ringed
Branched
Condensation reaction to form a
disaccharide
Which one of these uses chitin? Which one of these uses glycogen?
Functions of carbohydrates
• Provides quick energy in the form of glucose
• Can also be stored in the form of glycogen and
starch
• Can be used structurally as in plants
(cellulose) and some animals (chitin)