Download Carbohydrates and Energy

Carbohydrates (CHO) <carbons, with water attached to them
(carbo-hydrate)>
-carbohydrates contain only Carbon, Hydrogen and Oxygen
-carbohydrates are produced in the process of photosynthesis
Carbohydrates and Energy
-main energy source for living things
-energy is stored for short term or long term
-CHO include sugars, starches, cellulose and chitin
-energy stored in chemical bonds that hold
carbohydrates together
-this energy is then used in any activity that the
organism does
The Structure of Carbohydrates
Remember, all macromolecules are composed of monomers that join together in a
deydration synthesis reaction to from polymers.
Carbohydrates
Monomer(s)
Monosaccharides
Disaccharides
Polymers
Polysaccharides
Starch
Cellulose
Chitin
Glycogen
Types of CHO:
-CHO are classified based on the
number of simple sugars that they
contain and there are three types of
carbohydrates according to complexity
Monosaccharides
-sweet tasting, simple sugars
-have 6 carbon atoms and some
hydroxyl groups
-soluble in water (they dissolve in
water)
-the three most common
monosaccharides are:
a)Glucose
(main sugar)
b) Galactose
(sugar found in milk)
c) Fructose
(sugar found in fruits)
Disaccharides/Double Sugars
-consist of two monosaccharides
linked together (a dehydration
synthesis reaction links them
together)
-the hydroxyl (OH) group of glucose
reacts with the hydroxyl (OH) group
of fructose
-soluble in water (they dissolve in
water)
http://www.biotopics.co.uk/as/disaccharideformation.html
-good animation of a condensation reaction
Polysaccharides (Many Sugars)(three or more monosaccharides)
-macromolecules that are polymers of a few hundred/thousand monosaccharides
-NOT soluble in water (do not dissolve in water)
-have two important biological functions
1. Energy Storage (Starch and Glycogen)
Glycogen
2. Structural Support (Cellulose and Chitin)
-animals store glucose in the form
of glycogen in the liver and
muscles to be used as quick
energy
-consists of hundreds of glucose
molecules strung together in a
highly branched chain
Starch
-plants store energy in the form
of starch
-found in rice, wheat, potatoes,
flour,
-too large to be absorbed by our
digestive system- we have to
break them down into
monosaccharides
Cellulose
-a large polysaccharide found in the cell walls of plants
-provides structure, protection, rigidity and support
-makes up about 50% of wood
*humans do not have the bacteria necessary to digest cellulose, therefore it is
not a direct energy source for us, that is why we can’t eat hay
-makes up wood and paper
-we don’t digest it so it goes through us undigested, but it does attract water,
and mucus and helps to prevent constipation. Fibre is healthy!
Chitin
-makes up the exoskeleton of insects and crustaceans
-tough material, we don’t digest it well
-used to make contact lenses and stitches!