Macromolecules

Macromolecules
Carbohydrates,Proteins,
Lipids, and Nucleic Acids
Chapter 2

• Carbon, hydrogen, oxygen, and nitrogen make up
96% of living things. Sulfur and phosphorus are also
important.
• Organic compounds-compounds that contain carbon.
-All organisms are organic.
-Because Carbon has 4 valence electrons, it can
form many types of molecules.

• Macromolecules-”giant” molecules
• molecules with many carbon atoms joined
together by polymerization-building a polymer.
• monomer-single molecule that can combine
with other monomers to form polymers
-the order, number, and type of monomers
combined, allows many types of polymers to be
formed.
• polymer-large molecule formed when many
monomers bond together in various ways. Energy is
stored in the bonds of polymers.
Methane Acetylene Butadiene Benzene Isooctane

• condensation (dehydration synthesis)-when
an –H and an –OH are removed from 2
monomers to form a water (H 2
O) molecule and
build a polymer
• hydrolysis-breaking apart a polymer by adding
a water molecule. An -H and an -OH attach to
the bonds between monomers in a polymer.
-takes place in the digestion of
food to break down polymers. The stored
energy is released when these bonds are
broken and is used to power daily functions.

1. Carbohydrates=Sugars
•made of carbon, hydrogen, and oxygen in
the proportion of 1:2:1
-general formula is (CH 2
O) n
where n is the
number of carbon atoms.
-product of photosynthesis
-store and transport energy in the bodies of living
things
-monosaccharides (monomer)-one sugar molecule
(ex-glucose, galactose, and fructose)-quick
energy
-disaccharide-made of two sugar molecules
(ex-sucrose or table sugar)

-polysaccharides-made of many sugar molecules. Larger
so provide us with more energy than do other types of
carbs.
-examples
1. starch-food storage product in plants
2. glycogen-supplies the energy for muscle
contraction in animals
3. cellulose-forms the cells walls of plants and makes
them rigid. Animals can’t digest cellulose but it is
necessary in our diets for digestion and the elimination of
waste. Known as fiber.
4. chitin-forms cell wall of fungal cells and exoskeleton
of arthropods

Polymer
Starch
Glucose
Monomer

2. Lipids
• made of carbon, hydrogen, and oxygen----have less
oxygen than carbohydrates
•Ex-fats, oils, waxes, cholesterol, and chlorophyll-molecule
that collects sunlight for photosynthesis
•Nonpolar so insoluble in water
•used for long-term energy storage, metabolic reactions,
insulation, and protective coatings (ex-plasma membrane)
• triglyceride-most common type of lipid, consists of 3 fatty
acids bonded to a molecule of glycerol
-glycerol-a 3-carbon molecule that serves as a backbone
for the lipid molecule

Glycerol
3 Fatty acid chains

-saturated lipids vs. unsaturated lipids-
-saturated lipids have carbon chains with single bonds of carbon
and hydrogen atoms. They have the maximum number of these
bonds and maximum amount of hydrogen (saturated with
hydrogen). These are usually solid at room temperature (ex-butter
and steak)
-this is the “bad” fat. The more hydrogen a fat molecule
has, the worse it is for your body
-unsaturated lipids have carbon chains with double or triple bonds
between carbon atoms. Fewer hydrogens can bond to carbon due to
the double bonds.
-since less hydrogen can bond here, these are better for you
and are liquid at room temperature

3. Proteins
•polymer of carbon, hydrogen, oxygen, nitrogen,
and sometimes sulfur.
-perform most functions in bodies of organisms and
control the expression of traits
-examples-enzymes, hair, muscles, spider's web,
collagen fibers in skin, tendons, ligaments, and bones
(support and structure…we don’t metabolize them for energy)
-amino acids (monomer)-the basic building blocks
of proteins. There are 20 amino acids.
-more types of proteins than any other
macromolecule because there are so many
amino acids.

-peptide bond-bond formed between amino acids to
make a protein
-proteins are also called polypeptides because
there are “many” of this type of bond in a protein
-enzymes-proteins that act as a catalyst to speed up
the rate of a chemical reaction. In some cases it
allows some reactions to take place in a cell that
normally would need very different conditions.
Amino
acids

4. Nucleic Acids
-composed of carbon, hydrogen, oxygen, nitrogen, & phosphorus
-macromolecule that stores hereditary information in a code that can be
translated to form new proteins. Long chains of repeating monomers
called nucleotides.
-nucleotides-consist of a 5-carbon sugar with a phosphate group
attached to one side of the sugar and a base attached to the other side.
-DNA and RNA
1. DNA is the genetic information---determines everything
about an organism.
2. DNA serves as the template for RNA. RNA is used to
make proteins.