Carbon, hydrogen, and oxygen are the most common elements in living organisms and are parts of important organic macromolecules like carbohydrates, lipids, and proteins. Organic compounds contain carbon and are found in living things. They are made through condensation reactions joining smaller subunits like monosaccharides, amino acids, and fatty acids. Larger molecules can be broken down through hydrolysis reactions into these smaller subunits. Important macromolecules include starch, cellulose, glycogen and chitin which are made of repeating glucose units, as well as disaccharides like sucrose, lactose, and maltose.

1. Carbon, Macromolecules and
Carbohydrates
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2. Elements Found in Living Organisms
• Living organisms contain
many chemical elements,
some in large quantities
and some in very small
amounts
• The 3 most common
chemical elements of life
are carbon, hydrogen, and
oxygen (CHO)
• They are part of all the
main organic compounds
in living organisms
• Organic compounds:
– contain carbon
– found in living organisms
• carbohydrates, lipids,
amino acids are all organic
molecules 2

3. 3

4. Examples of Chemical Elements
and Their Roles
Element Role in Plants or Animals
Nitrogen Part of the amine groups of amino
acids and therefore proteins
Calcium Needed to make the mineral that
strengthens bones and teeth
Phosphorus Part of the phosphate groups in ATP
and DNA molecules
Iron Needed to make hemoglobin and
thus to carry oxygen in blood
Sodium Used in neurons (nerve cells) for
the transmission of nerve impulses 4

5. Organic Chemistry
• Study of carbon
compounds
• Occur in more
than just living
things
• Are typically made
by living things
– Organic
compounds come
from organisms
– The chemistry that
you study in HS is
inorganic
• Compounds that
are found in the
non-living world http://www.chemistryland.com/ElementarySchool/BuildingBlocks/BuildingOrganic.htm 5

6. Organic Compounds
• The molecules of many organic compounds are large and
may seem complex, but they are built up using small and
relatively simple subunits
YOU MUST BE ABLE
TO IDENTIFY THESE
STRUCTURES, you do
not have to be able to
draw them.
Fatty Acid
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7. Carbon Skeletons
• Vary in • Isomers have the same
– Length molecular formula
– Branching • Isomers varying in their
– Double bonds structures
– Rings – Have different properties
http://fig.cox.miami.edu/~cmallery/255/255chem/p2x1.jpg
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8. COPY THIS ENTIRE CHART!
small organic molecules 
larger organic molecules
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9. SUBUNITS MACROMOLECULES: MACROMOLECULE
ASSEMBLIES:
ex: sugars, ex: globular
amino acids, proteins and RNA ex: ribosome
nucleotides
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10. • In a condensation
reaction, 2 molecules Condensation Reactions
are joined together to
form a larger molecule
• Water is also formed in
the reaction
• For example, 2 amino
acids can be joined
together to form a
dipeptide by a
condensation reaction
• The new bond formed is
a peptide linkage
• Further condensation
reactions can link amino
acids to either end of the
dipeptide, eventually
forming a chain of many
amino acids
• This is called a
polypeptide 10
www.pearsonsuccessnet.com activity 5.1 page 2

11. Condensation Reactions
• In a similar way, condensation reactions can be used to
build up carbohydrates and lipids
• The basic subunits of carbohydrates are monosaccharides
• 2 monosaccharides can be linked to form a disaccharide
and more monosaccharides can be linked to a
disaccharide to form a large molecule a polysaccharide
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12. glycerol
+ 3H20
three fatty-acid triglyceride
tails
• Fatty acids can be linked to glycerol by condensation
reactions to produce lipids called glycerides
• A max of 3 fatty acids can be linked to each glycerol,
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producing a triglyceride

13. Hydrolysis Reactions
• Large molecules such as polypeptides, polysaccharides
and triglycerides can be broken down into smaller
molecules by hydrolysis
• Polypeptides + water  dipeptides or amino acids
• Polysaccharides + water  disaccharides or
monosaccharides
• Glycerides + water  Fatty acids + glycerol
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14. Monosaccharides
• glucose
• ribose
• deoxyribose
• fructose
• galactose
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15. 15

16. Disaccharides
COMPONENT
DISACCHARIDE DESCRIPTION MONOSACCHARIDES
SUCROSE COMMON TABLE SUGAR GLU + FRU
LACTOSE MAIN SUGAR IN MILK GALACTOSE + GLU
MALTOSE PRODUCT OF STARCH HYDROLYSIS GLU + GLU
CAN BE USED IN BEER FERMENTATION
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17. Starch
• repeating, branching
macromolecule
• carb storage for plants
– For energy
– Cellulose 17

18. 18

19. Glycogen
• storage of glucose in the liver and
muscle
– For energy
• animals only
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20. • forms exoskeleton of
Chitin arthropods: insects,
lobsters, shrimp,
spiders
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21. POLYSACCHARIDES
Polysaccharide Description Monomer Unit
• STARCH energy storage in plants α-glucose
• CELLULOSE structure of plant cell walls β-glucose
• GLYCOGEN energy storage in animals α-glucose
• CHITIN structure of fungi cell walls & β-glucose
exoskeleton of insects
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