An Introduction to
Organic Molecules
Organic Molecules
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Organic molecules
are made primarily
of four elements : C,
N, O, H
Backbone is C
Polymers are built
of small units called
monomers.
Monomers and Polymers
Monomers
Polymers
Monosaccharide
Polysaccharide
(Fatty acids)+glycerol
Lipids
Amino acid
Protein
Nucleotide
Nucleic acid
Monomers Build Polymers
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Polymers are built
through a process
called dehydration
synthesis.
Dehydration Synthesis builds
POLYMERS
Breaking Down Polymers
• Polymers are broken
down through a
process called
hydrolysis.
Hydrolysis breaks down
POLYMERS
The FOUR major organic
compounds (polymers):
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Carbohydrates
Lipids
Proteins
Nucleic Acids
Carbohydrates - all types of
sugars
Monosaccharides : Simple
Sugars
• All monosaccharides
have the basic
chemical formula
CH2O
• Function: Immediate
Energy!!!
Common sugars are glucose,
fructose and galactose.
Disaccharides :
Double Sugars
 All disaccharides
are made of 2
monosaccharides
linked together
 Function: Energy
Polysaccharides :
Complex sugars
(aka. Complex carbs)
• All polysaccharides
are built of
monosaccharides
• Two functions of
polysaccharides are
storage and
structure.
Energy Storage
Polysaccharides
Starch: plant
Glycogen : animals
Structural Polysaccharides
Cellulose : plants
Chitin: animals (invertebrates)
Review of Carbohydrates
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Monomers :
Polymers:
Structure:
Functions:
Proteins
Proteins - chains of amino acids
• Proteins make up 50% of
the dry weight of most
cells (that’s a LOT!!)
• Proteins build structure
and carry out cell
metabolism
• Proteins are built of
amino acids.
• There are 20 types of
amino acids.
Types of Proteins
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Structural
Storage
Transport
Hormonal
Contractile
Antibodies
Enzymes
Structural :
elastin, collagen, keratin
Storage :
ovalbumin
& casein
Transport :
hemoglobin & membrane proteins
Hormonal :
insulin & growth hormones
Contractile :
actin & myosin (both in muscle
fibers)
Enzymes (speed up chemical
reactions):
amylase & protease
Review of Proteins
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Monomers :
Polymers:
Structure :
Functions :
LIPIDS
Polymers that don’t mix with water!
This means they are hydrophobic.
Groups are FATS, PHOSPHOLIPIDS
& STEROIDS
Fats = 1 Glycerol + 3 Fatty
Acids
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Fats are large molecules made of 2 monomers : glycerol
+ fatty acids.
There are two types of fatty acids - saturated and
unsaturated.
Functions of fats include : insulation, energy storage,
shock absorber for internal organs (like bubble wrap!)
Saturated Fatty Acids
 Characteristics:
 Solid at room
temperature (can pack
together tightly)
 Mostly found in
animals
 No double bonds
between Carbons
(filled with Hydrogens)
 Examples :
Unsaturated Fatty Acids
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Characteristics
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Liquid at room
temperature (can’t pack
together tightly)
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Found mostly in plants
Double bonds found
between Carbons (not
filled with Hydrogens)
Examples :
Phospholipids = 2 Fatty Acids +
Phosphate
• Phospholipids are found in the cell membrane.
• Phospholipids have polar (charged) & nonpolar (not charged)
ends. The phosphate end is HYDROPHILIC. The fatty
acid end is HYDROPHOBIC.
• The unique structure (polar & nonpolar) contributes to the
function of these molecules in the cell.
Steroids = Carbon skeleton
with 4 fused rings
not just
anabolic
steroids!!
• Steroids are a natural and important components of the cell
membrane in many organisms.
• An example is cholesterol - found ONLY in animal tissues.
It is used to help construct other important hormones in
organisms.
Steroids (continued)
• Examples of hormones
created using steroids are
estrogen, progesterone and
testosterone.
• Anabolic steroids are a
synthetic form of
testosterone to increase
muscle mass. Both men
and women who take
testosterone increase the
masculine physical
features normally
triggered by varied levels
of testosterone in the
body.
Review of Lipids
• Monomers of FATS:
• Functions of fats:
• Monomers of
PHOSPHOLIPIDS:
• Functions of
phospholipids:
• Structure and function
of steroids:
Nucleic Acids:
the polymers built of
nucleotides
DNA
RNA
Nucleotides - the building
blocks of nucleic acids
DNA - deoxyribonucleic acid
• Characteristics
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Double helix
Four nitrogenous bases : A, T, C, G
Deoxyribose sugar (5-carbon sugar)
Function : storage of genetic codes
RNA - ribonucleic acid
• Characteristics
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Single stranded
Four nitrogenous bases - A , U, C, G
Ribose sugar (5-carbon sugar)
Function : transcribe and translate DNA into proteins
Review of Nucleic Acids
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Monomers :
Polymers :
Structures:
Functions :