1. Concept 5.2: Carbohydrates provide fuel and building material

2. Counting “Carbs” (aka Sugars)
Carbohydrates contain carbon, hydrogen, and oxygen in the ratio: 1C : 2H : 1O
Basic molecular formula: CH2O.
Usually found as carbon skeletons that have a ring shape.

3. Which of the following is NOT a valid formula for a carbohydrate?
Basic molecular formula:
CH2O
“carbo”
(carbon)
“hydrate”
(water)

4. Carbohydrates Come in Many Forms
Monomer = Monosaccharides
Example: Glucose (C6H12O6)
Dimer = Disaccharides
Example: Sucrose (C12H22O11)
Polymer = Polysaccharides
Example: Starch

5. What is the name of this carbohydrate?
starch
glucose
sucrose
fructose
Note the six carbon atoms in
a ring-shaped arrangement.
Glucose: C6H12O6

6. Lactose is a monosaccharide.
True
False
Lactose
Lactose is a disaccharide
composed of two
monosaccharides: glucose &
galactose.
People who are
“lactose intolerant”
are unable to
metabolize lactose.
MILK

7. Glucose is hydrophilic.
True
False
This is due to its many hydroxyl groups. Recall that the
hydroxyl functional group attracts water. Therefore,
monosaccharides and disaccharides dissolve readily in
water, forming sugary solutions. Starch and cellulose do
not dissolve readily, but they do attract water.

8. Functions of Carbohydrates
Short Term Energy
Monosaccharides (plants & animals)
Example: fructose
2) Long Term Energy
Polysaccharides
Starch (plants)
Glycogen (animals)
3) Structure
Cellulose (plant cell walls)
Chitin (animal exoskeletons)
potatoes
turkey
cellulose
chitin

9. Examples of Polysaccharides

10. Which of the following carbohydrates would you NOT expect to find in a plant?
chitin
starch
glucose
cellulose
Chitin is found in the exoskeletons
of arthropods like this spider, not in plants.