Macromolecules of Life
Organic v. Inorganic
 Organic molecules are carbon based;
they are the second most common
molecules found in living things next to
water.
 Inorganic molecules are not carbon
based. (exceptions: CO2).
 Organic molecules can fall into four
groups of macromolecules
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Carbohydrates
Lipids
Proteins
Nucleic Acids
 They are each composed of multiple
monomers, single units, that are
bonded together to form polymers,
many units bonded together.
Condensation/Dehydration Reaction –
Producing a Polymer
 When two monomers
come together to make
a polymer they
undergo a
condensation/
dehydration
reaction.
 The two join to make
one molecule and end
up. producing a water
Hydrolysis – Breaking a Polymer into Monomers
 When a polymer is
broken down into its
monomers it undergoes
a hydrolysis
reaction.
 Here water is added to
break apart a polymer.
Polar and Nonpolar Molecules
 Nonpolar molecules have an
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evenly distributed charge. They are
called hydrophobic or water
fearing.
Polar molecules have an uneven
distribution of charge. They are
hydrophilic or water loving.
Most macromolecules of life start as
hydrocarbons, molecules composed
of C and H.
Hydrocarbons are nonpolar which
creates an issue since our bodies
are predominantly made of water.
Therefore, a functional group is
added to change the various
characteristics of a molecule to
make it polar.
Functional Groups
Carbohydrates
 Elements: C, H, O – distinguishing fact, always occur
C,H2,O
 Monomer: monosaccharides; C6H12O6 isomers
Carbohydrates
 2 monosaccharides make a
disaccharide
 More than 2 monosaccharides make
a polysaccharide
 Examples and functions:
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(M) Glucose – source of energy for the body
(D) Sucrose – quick source of energy
(P) Glycogen – stored energy, many linked
glucoses
(P) Cellulose – component of the cell wall
(P) Chitin – Exoskeleton of insects and
crustaceans
Lipids
 Elements: C, H, O –
distinguishing feature is that
they have large amounts of C
and H but little O. They are
nonpolar and insoluble.
 Monomers: fatty acids and
glycerols
Lipids
 Examples and functions of each
type
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FA - 2 types: Saturated and
Unsaturated. Saturated have as many
hydrogens bonded to the central
carbons as possible. Unsaturated do
not have as many hydrogens as
possible because carbon made a double
bond. Saturated are extremely
unhealthy for humans because they can
clog arteries.
Phospholipids are important because
they build the cell membrane of every
kind of cell.
Triglycerides are fats – found in human
blood and can contribute to heart
disease
Steroids are not all bad. Some
examples are cholesterol, estrogen and
testosterone
Proteins
 Elements: C, H, O, N, and S –
distinguishing element is S
 Monomer: amino acid; there are
20.
 Components of an amino acid:
 Two amino acids are joined by a
peptide bond
Proteins
 The order, number, and
types of amino acids are
what makes different
proteins.
•
Examples: Proteins have different
functions
 Hemoglobin – carries oxygen
on the red blood cells.
 Insulin – regulates blood sugar
 Enzymes ~ Enzymes typically
end with -ase; lactase, sucrase,
polymerase; speed up chemical
reactions
Proteins
 There are 4 levels to the structure of a protein
 Primary – combination of amino acids
 Secondary – structure that the amino acids build – sheets and
helixes
 Tertiary – globular (3-D) shape that they take
 Quaternary – when 2 or more join together
Nucleic Acids
 Elements: C, O, H, P, N –
distinguishing element is
P
 Monomer: nucleotides. It
is composed of a 5 C
sugar, a Phosphate group,
and a nitrogenous base
Nucleic Acids
 DNA (Deoxyribonucleic
Acid) – genetic information;
has deoxyribose as its sugar
 RNA (Ribonucleic Acid) – a
copy of the genetic
information that makes
proteins; has ribose as its
sugar.
 Five Nitrogenous bases:
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Adenine (both DNA and RNA)
Thymine (only DNA)
Guanine (both DNA and RNA)
Cytosine (both DNA and RNA)
Uracil (only RNA)