Important
MACROMOLECULES
(“Large Molecules”)
Used in Biological Systems:
Carbohydrates
Lipids
Proteins
Nucleic Acids
What Are They???
Carbohydrates, Lipids, Proteins, and
Nucleic Acids are the 4 major classes of
organic compounds in cells.
Because these are very large molecules
and very important in Biological
Systems, we refer to these 4 classes of
organic compounds as the
MACROmolecules of Life.
Important Terminology
Compound: Two or more DIFFERENT
molecules combined.
Example: Water molecules bound together with hydrogen
bonds are NOT compounds
Example: Sucrose (table sugar) is a compound. (More than
one type of molecule present.
Mixture: Two or more DIFFERENT
compounds combined.
Organic: Any molecule that contains a carbon
atom.
**All of the macromolecules discussed in this presentation are organic**
Important Terminology (cont.)
Monomer:
Simplest single-carbon component of a
compound or macromolecule.
Dimer:
Two monomers combined.
Polymer:
Many monomers combined to form a large
“macro” molecule
Composition of Macromolecules
Elements Involved:
Carbon
Hydrogen
Oxygen
Nitrogen
Phosphorous
Formulas:
Carbohydrates = CH2O
Lipids = CHO
Proteins = CHON
Nucleic Acids = CHONP
 ALL OF THESE MACROMOLECULES ARE ORGANIC
Composition of Macromolecules
(continued)
Monomers Involved:
1. Carbohydrates: monosaccharides
2. Lipids: glycerol and fatty acids
3. Proteins: Amino Acids
There are 20 Amino Acids used to make
proteins in mammals.
4. Nucleic Acids: Nucleotides
Nucleotides consist of a nitrogenous base, a
phosphate group and a ribose sugar. There
are 5 known nucleotides.
CARBOHYDRATES (CH2O)
Monomers of carbohydrates: Monosaccharides
Carbon Water (C6H12O6 ==> CH2O)
Carbohydrates are Sugars!
Saccharide = greek word for sugar
Where saccharin (artificial sweetener) got its name
Carbohydrates usually end with the –ose suffix
Classification (Forms) of Carbs
Monosaccharide
One saccharide molecule
aka Simple sugars
monomers that comprise carbohydrates
Examples:
Glucose – used in Cellular Respiration
Fructose – fruit sugar
Galactose – part of Milk sugar
Ribose – part of DNA and RNA molecules
Classification (Forms) of Carbs (cont.)
Disaccharide
Two monosaccharides combined
Examples:
» Sucrose = Glucose + Fructose (table sugar)
» Maltose = Glucose + Glucose
(malted milk balls, ice cream malts)
» Lactose = Glucose + Galactose (milk sugar; lactation)
Classification (Forms) of Carbs (cont.)
Polysaccharide
Many monosaccharides combined
Very large molecules
Complex Carbohydrates
Examples:
Long chains
of glucose
»Glycogen – NRG storage in mammals
»Starch – NRG stored in plants; Pasta
»Cellulose – Paper; humans can’t digest
Uses of carbohydrates
Used as a primary source of NRG in
humans.
Strength and Rigidity in plants
Sweetener
Paper
Thickeners
Example of Medical use:
Heparin (polysaccharide)
» (Hep-lock)
• Used to prevent excessive blood clotting when
administering IV fluids in hospitals
LIPIDS (CHO)
Monomers of Lipids:
Fatty Acids and glycerol
Lipids are Fats!
Basic Elements:
CHO
Some Lipids are called “saturated” and some are
called “Unsaturated.”
Saturated: All 4 of Carbon’s possible binding sites are bound by atoms.
These are solids at room temperature. (Examples: Vaseline, Wax,
Shortening)
Unsaturated: Not all of Carbon’s possible binding sites are bound by other
atoms. Carbon will then form double bonds with other Carbon atoms. These
are liquids at room temperature (Examples: Cooking Oil, gasoline)
Forms of Lipids
Triglyceride = glycerol + fatty acid chains
Lipids are stored in humans as triglycerides
Fatty acids have two regions
» Hydrocarbon chain
» Carboxyl group (COOH)
Steroids
Cholesterol
Bile salts
Male and female sex hormones
– Estrogen and Progesterone
– Testosterone
Wax
Phosopholipid – Part of Cell membrane
Prostaglandins
Raise and lower blood pressure
Contract smooth muscle (blood vessels, intestines)
Uses of Lipids
Used as a Secondary source of energy in humans
Construction of Cell Membranes
Helps to maintain Homeostasis (prostaglandins)
Protective Coatings
Waterproofing agents; Car Wax
Cooking
Petroleum Products
Gasoline; Paint Thinner; Vaseline
Candles
PROTEINS (CHON)
Monomers of proteins: Amino Acids
Basic Elemental Components:
CHON
20 Amino Acids found in Mammals
Example of amino acids:
Glycine
Leucine
Amino acids usually end in –INE
PROTEINS & AMINO ACIDS
• Single carbon amino acids = Peptides
– Peptides are bound together to make DIPEPTIDES
(2 peptides) or POLYPEPTIDES, (more than 2).
• The covalent bond between 2 peptides is
called a Peptide BOND.
• Proteins are chains of amino acids AND
Polypeptides are chains of amino acids!
• PROTEINS = POLYPEPTIDES!!!
Phe
Met
Leu
Lys
Trp
More on Proteins
Proteins are Temperature dependent!
High temperatures will “Denature” proteins, which means they will
break down, lose their shape, and cease to function
Low Temperatures cause proteins such as enzymes to function less
efficiently.
The Optimal temperature for Protein function is body temperature.
Body temperature is 98.6mF or ~32mC
Example:
Fevers are dangerous because proteins such as enzymes will stop
functioning if temperature goes to high
Fresh vs. Canned Pineapple in Gelatin
» Enzyme (Bromelain) found in fresh pineapple breaks down
protein
» Gelatin is a Protein.
» Mix fresh pineapple in Gelatin: Gelatin won’t set
» Use canned pineapple: Gelatin will set. Why?
• Pineapple is heated during process of canning, which
denatures bromelain
Forms of Proteins
Muscle tissue:
Proteins are stored in the body as muscle tissue
Last energy reserve but can be used as an NRG source if
neither Carbohydrates nor Lipids are available.
Enzymes = Proteins
Act as catalysts for bodily reactions, which help
reactions occur easier, faster, and with less energy.
Plant Proteins: Gluten
Example: Whey and Soy Protein
Enzyme and Substrate
Uses and Examples of Proteins
Tertiary Energy Source in Humans
Facilitate Reactions (Enzymes)
Aid in Digestion (Enzymes)
Coded for by DNA and RNA
Examples (Forms):
Insulin
» Some diabetics don’t produce this
Lactase
» People who are Lactose Intolerant don’t produce this
Amylase
» Found in saliva; breaks starch into individual glucose
» Makes potatoes sweet if you keep them in your mouth long
enough
NUCLEIC ACIDS (CHONP)
Monomers of Nucleic Acids: Nucleotides
Elements: Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorous
Five nucleotides; Four in each of the nucleic acids DNA
and RNA
Cytosine
Thymine
Adenine
Guanine
Uracil(replaces thymine in RNA)
FORMS: DNA and RNA
What does DNA and RNA stand for?
DNA= Deoxyribonucleic Acid
RNA= Ribonucleic Acid
FUNCTION: Stores Genetic information that codes for all
the proteins in your body.
Used as a template or blue-prints to build proteins.