All living organisms require several
compounds to continue to live.
 We call these compounds biomolecules.
All of these biomolecules are organic,
which means that they contain carbon.

› Carbon has four valence electrons, which
means this element forms strong covalent
bonds with many other elements.

All of our biomolecules are classified into
four groups:
› Carbohydrates
› Lipids
› Proteins
› Nucleic Acids

Each of these classes have different
structures and functions.
Also, our biomolecules
are formed by joining
many small units
together to form a
long chain.
 This process is called
synthesis. Often, a
water molecule is
removed in the
process.

› When this happens,
we call it dehydration
synthesis.

The smallest functioning unit of a
biomolecule is a monomer.
› “Mono-” means ONE.

Put two monomers together, and you
get a dimer.
› Di-” means TWO.

Once several monomers are put
together, we get a polymer.
› “Poly-” means MANY.


Carbohydrates
(carbs) are
biomolecules used
for energy and
structural support.
Breaking carbs down
provides us with
energy.


Carbohydrates are
made up of carbon,
hydrogen and
oxygen.
The ratio of these
elements is roughly
1carbon: 2 hydrogen
:1 oxygen.



Monomer:
Monosaccharide
Dimer: Disaccharide
Polymer:
Polysaccharide



Carbs are primarily
used to provide us
with energy.
All monosaccharides
and dissachardies
end in “-ose”.
Glucose is used as a
common energy
source for most living
organisms.

There are many
other types of carbs
in nature:
› Fructose (fruit sugar)
› Lactose (milk sugar)
› Sucrose (table
sugar)
› Ribose/Deoxyribose
(important for DNA
and RNA)

Carbs can be
bonded to each
other through
dehydration
synthesis.
› Remember, that’s
when water is lost as
two smaller
molecules bond to
form a larger
molecule.



When we have
excess carbs, we
store them as
starches, which are
polysaccharides.
Starches are long
chains of carbs.
Plants also use
cellulose (another
polysaccharide) for
structural support.


Indicators are
chemicals that
detect the presence
of a certain
compound.
Benedict’s solution
reacts with MOST
mono- and
disaccharides.
› Sucrose is a notable
exception!

If a detectable
carbohydrate is
present, then the
indicator changes
color, based on how
many carbs are
present.
› Green → Yellow →
Orange → Red

This is useful for
diagnosing diabetes.

Iodine is used to
detect starch, since
it reacts readily with
starch.
› This reaction
produces a purpleblack coloration.
A ________ is made up of several smaller
units, or monomers.
2. What are the two primary uses of
carbohydrates?
3. Carbs can be identified because they
end with the suffix ______.
4. ________ is the common energy source
form almost all life on Earth.
5. Excess carbs are stored in our bodies as
________.
1.

1.
2.
Use the diagram to
solve the problems:
Lactose is an
example of what
type of carb?
What process joined
these two carbs
together?

Lipids are used for
four crucial
purposes:
› Storing energy
› Waterproof barriers
› Chemical
messengers
› Insulation


Lipids are made up
of carbon, hydrogen
and oxygen.
The ratio of these
elements is roughly
1carbon: 2
hydrogen. Oxygen is
present only in trace
amounts.



Most common lipids
are composed of
two different
functional groups:
Glycerol, an alcohol
with three oxygen
groups.
Fatty acids, which
are long
hydrocarbon chains.

ALL lipids repel
water, due to how
hydrophobic they
are. This means that
they do not bond to
water molecules.


Lipids are grouped by
the number of double
bonds found in the
hydrocarbon chain.
Saturated fats have
the maximum number
of hydrogen atoms
possible, and as such,
they have no double
bonds.
› They tend to be solid
at room temperature.

Unsaturated fats
have double bonds.
They do NOT have
the maximum
possible number of
hydrogen atoms.
› They tend to be
liquid at room
temperature.


Monounsaturated
fats have only ONE
double bond.
Polyunsaturated fats
have MORE THAN
ONE double bond in
the hydrocarbon
chain.
Polyunsaturated
Monounsaturated


It’s important to note
that fats are a
specific type of lipid.
Chemically, all fats
are triglycerides –
they have three fatty
acids bonded to one
glycerol molecule.


Steroids are lipids
with four rings
bonded together.
Steroids are vital as
hormones, which are
chemical signals
used in the body.

Oily and fatty foods
tend to leave stains
upon contact.

› This is why we can

use brown paper to
detect fats.
We can also use
ethanol, which
dissolves lipids.
The dissolved fats are
then diluted with
water. Since water
and lipids don’t mix,
the lipids come out
of solution.
› This creates an
emulsion – a milky,
cloudy liquid.
Show the ratio of carbon : hydrogen :
oxygen in lipids:
2. All lipids are [hydrophilic, hydrophobic].
3. True or false: Saturated fats have no
double bonds, and the maximum
number of hydrogen atoms.
4. Monounsaturated fats have __________
double bond(s).
5. _________ serve as hormones.
1.

Proteins serve many
vital functions in your
body:
› Structural support
› Speeding up
chemical reactions
› Transport of
molecules
› Fighting infection
› …and many more!


All proteins contain
carbon, hydrogen,
oxygen and
nitrogen.
In addition, sulfur
may be present as
well.


Monomer: Amino
acid
Polymer: Protein or
polypeptide
› A peptide is a chain
of amino acids, so a
polypeptide is
several chains put
together.


ALL amino acids
contain an amino or
N-group. It contains
nitrogen (N).
ALL amino acids also
contain a carboxyl
or C-group. It
contains carbon (C).

However, amino
acids also have a
variable group or Rgroup. This differs
from one amino acid
to the next.
› There are 20
standard amino
acids, and thus 20
possible R-groups.

Amino acids are
bound together
through dehydration
synthesis.
› The C-group of one
amino acid binds to
the N-group of
another.
› We call these bonds
peptide bonds.

Proteins have four phases of production:
› Primary: Amino acids are bound together.
› Secondary: Individual amino acids are bent
and molded as needed.
› Tertiary: The entire chain of amino acids is
bent and molded as needed, forming a subunit.
› Quaternary: Multiple completed sub-units
are fitted together to make a complete
protein.

Protein can also
function as hormones.
› However, protein
hormones tend to
have difficulty passing
the cell membrane.

As such, many protein
hormones have to fit a
cellular receptor
before they can affect
the cell.



The Biuret test is used
to detect protein.
First, protein is
dissolved in water.
Then, a strong base
is added to the
solution.
Finally,
1.
2.
3.
What biomolecule is
being built?
Amino acids are
bonded together in
the _________ step
of production.
Amino acids are
held together with a
_________ bond.
Hydrolysis is the reverse process of
dehydration synthesis.
 In dehydration synthesis, water is lost to
create a bigger molecule.
 In hydrolysis, water is ADDED, and a
bigger molecule is broken down into
smaller pieces.

› Hydrolysis = hydro and lysis. Hydro means
water, and lysis means to break down.


Nucleic acids are
biomolecules that
contain the
blueprints for making
proteins. Nucleic
acids also transmit
genetic info to the
next generation.
Includes:
› DNA
› RNA


Nucleic acids
contain carbon,
hydrogen, oxygen,
nitrogen, and
phosphorus.
Remember the
acronym: CHONP!


Monomer:
Nucleotides
Polymer: Nucleic
Acid

A nucleotide is
made up of three
parts:
› 5-carbon sugar
› Phosphate group
› Nitrogenous base

A nucleoside,
however, is the sugar
and the base
WITHOUT the
phosphate.


The 5-carbon sugar is
deoxyribose, in the
case of DNA.
However, it is ribose
in the case of RNA.
› This is how those
molecules got their
name!


The fifth carbon of
the sugar is bonded
to a phosphate
group. Thus, we say
that this is the 5’ end.
The third carbon of
the sugar is bonded
to an OH group. This
is called is the 3’
end.
As stated earlier, nucleic acids are the
blueprints for proteins. Proteins are made
from these templates.
 Also, DNA can be passed on from parent
to child. This allows SOME characteristics
to be passed down to offspring. These
traits are considered hereditary.
 RNA can NOT be passed down to
offspring, however!

The monomer of a nucleic acid is a
____________.
2. All nucleotides contain which three
components?
3. DNA carries information down from
generation to generation. This
information is _____________.
4. DNA and RNA contain which elements?
1.