What are polymers?
All living things are composed of organic (carbon-based) molecules.
The four major groups of organic
carbohydrates, lipids, proteins,
Each of these molecules, although
structurally and functionally different, has a common tie in their manufacture: each molecule is comprised
, which have been combined via
condensation or dehydration
or loss of water. All of the biologically important molecules discussed in this portion of the lab
are created by the removal of one molecule of water between monomers.
Formation of a polymer through a condensation reaction (a.k.a. dehydration
What are monosaccharides (1 sugar), disaccharides (2 sugars), polysaccharides (many sugars)?
Carbohydrates are classified by the number of individual sugar molecules that they contain.
equal numbers of carbon and oxygen atoms (n)
twice that number (2n) of
An approximate chemical formula for a typical carbohydrate is
is an integer (3, 4, 5, etc.).
The most common monosaccharides or simple sugars are the six carbon sugars known as
, the most important one being glucose. They all have the same molecular
but slightly different structural formulas and slightly different chemical properties.
Monosaccharides bonded through dehydration synthesis form disaccharides through one glycosidic
contain two sugar monomers.
Disaccharides such as
(glucose + glucose),
sucrose or table sugar
(glucose + fructose)
lactose or milk sugar
(glucose + galactose) have the same molecular formula, C
different structural formulas and slightly different chemical properties.
Polysaccharides, such as starch, glycogen, cellulose, and chitin
, contain many sugar monomers
is a polysaccharide produced by plants.
is a polysaccharide
produced by animals. These molecules are large and are usually
insoluble in water.
What are Reducing Sugars?
Reducing sugars are carbohydrates that, when combined with a specific chemical reagent called
are participants in an oxidation-reduction (redox) reaction with the Benedict’s.
When combined with the chemical reagent Benedict’s, the
reducing sugar is
during the reaction. The Benedict's reagent contains blue
which is reduced to red
O) by the reducing sugar.