The document discusses the four major classes of chemical compounds found in living organisms: carbohydrates, nucleic acids, proteins, and lipids. It provides examples and functions of important molecules within each class, including how they are constructed from smaller building blocks and bonded together. Key molecules like ATP store and transfer energy through bonding, while lipids like fatty acids store energy and form biological membranes.

1. The Chemical Building Blocks
of Living Systems
• There are four major classes of chemical compounds found
in living organisms:
-Carbohydrates
-Nucleic Acids
-Proteins
-Fats and Lipids
• Carbon is the predominant element in living systems.
• Carbon can form covalent bonds with up to four atoms.
• All carbon-containing compounds in living organisms are
called organic compounds.

2. Examples of Carbon-containing Molecules

3. Important Functional Groups
• Groups of covalently
linked atoms that
have specific
chemical properties
wherever they are
found.

4. Complex Structures From Smaller Components
• Small carbon-containing
molecules can either remain
as individual molecules or
bond with other small
molecules to form larger
structures called
macromolecules.
• Monomers are individual
small molecules with 20 or
fewer atoms.
• A polymer is a collection of
hundreds of monomers.

5. Dehydration Synthesis and Hydrolysis
• Dehydration synthesis (condensation reaction):
Simple molecules are joined together to form larger
molecules by the removal of water.
Energy is stored in the bond created between the
simple molecules.
• Hydrolysis:
Larger molecules are separated into simple
molecules by the addition of water.
Energy is released by breaking the bond between
the simple molecules.

6. Dehydration Synthesis (Condensation Reaction)
More examples at:
http://science.nhmccd.edu/biol/dehydrate/dehydrate.html

7. Carbohydrates
Examples:
Sugars and starches
Made up of Carbon, Hydrogen, and Oxygen
C:H:O = 1:2:1
Building blocks:
Monosaccharides (simple sugars).
Function:
Primary source and storage of energy.

8. Carbohydrates
2 Monosaccharides  1 Disaccharide
Monosaccharides have the chemical formula C6H12O6.
Examples: Glucose, Galactose and Fructose.
Dissacharides are made up of two monosaccharides joined
together and have the chemical formula C12H22O11.
Examples: Maltose = Glucose + Glucose
Sucrose = Glucose + Fructose
Lactose = Glucose + Galactose

9. Carbohydrates
Polysaccharides:
Made of a chain of
monosaccharides.
Examples:
• Cellulose forms strong
parallel fibers that
help support the leaves
and stems of plants.
• Starch stores energy in
plants.
• Glycogen stores energy
in the liver and
muscles of animals.

10. Sweet Facts

11. Nucleotides
Examples:
DNA and RNA
Consist of linked rings of atoms (C, H, O, P and N).
Building blocks:
• Nitrogen containing base (adenine, cytosine, guanine,
thymine, and uracil
• Sugar ring (deoxyribose in DNA and ribose in RNA)
• Phosphate group (1, 2 or 3 can bond to the sugar)
Function:
Stores genetic information for every cell in an organism.
Involved with energy transfer (ex. ATP)

12. Nucleotides – Store and Transfer Information
In DNA
A bonds to T
G bonds to C
The bases bases
also bond to
deoxyribose
In RNA
A bonds to U
G bonds to C
The bases also
bond to ribose
Nucleotides join together to form the rungs of a
twisted ladder shape called a double helix.

13. Nucleotides – Store and Transfer Energy
ATP is made up
of an adenine
base, a ribose
sugar and 3
phosphate
groups.
Energy is stored in the covalent bonds that link its 3
phosphate groups together.
The breaking of the bond between the second and third
phosphates releases energy, which can be used to
drive other chemical reactions.

14. Amino Acids are the Building Blocks of Proteins
There are 20 different
amino acids.
Each has an amino group,
a carboxyl group and a
different side chain (R
group) bonded to a
central carbon.

15. Amino Acids are the Building Blocks of Proteins
T form proteins, chains of
amino acids link
together by covalent
bonds between the
amino group of one
amino acid and the
carboxyl group of
another.
Each protein folds into a
unique 3-D structure
largely determined by
the interaction of the R
groups of the protein.

16. R Groups Give Each Amino Acid
Specific Chemical Properties
Nonpolar or uncharged and are repelled by water.

17. R Groups Give Each Amino Acid
Specific Chemical Properties
Polar or
charged
and can
interact
with water.
Unique chemical properties

18. The Importance of Proteins

19. Proteins That Can Take the Heat
• When heated, most proteins unfold.
• Proteins from thermophilic bacteria have given scientists clues
about what makes a protein thermostable.
• Understanding how the chemical properties of amino acids
define protein shapes has allowed biologists to engineer
proteins that are more stable.

20. Fatty Acids Store Energy and Form Membranes
• Composed primarily of long chains of C and H called
hydrocarbons and end with a carboxyl group.
• Key components of fats and lipids.
• Functions:
Fats Long-term energy storage.
Lipids  Main component of biological membranes.

21. Fatty Acids
Saturated Unsaturated
All the carbon One or more of
atoms are the carbon
linked
atoms are
together by
single linked together
covalent by double
bonds. covalent bonds.
Can pack Do not pack
tightly tightly together
together and and tend to
tend to form form liquids.
solids.
Examples: Example:
fats & waxes oils

22. Three Fatty Acids Bond to Glycerol
A single molecule of
glycerol can be
covalently linked to 3
fatty acids to form a fat
molecule.
Glycerol tristearate is the
most common fat
storage molecule.
Fats contain significantly
more energy than an
equal amount of
glucose.

23. Steroids
– Steroids are very different from fats in structure and
function.
• The carbon skeleton is bent to form four fused rings.
– Cholesterol is the “base steroid” from which your body
produces other steroids.
• Example: sex hormones

24. Phospholipids Form Bilayer Membranes in Water