There are four classes of
biological macromolecules:
Proteins, lipids, carbohydrates
and nucleic acids
Before you can understand the topics in this
unit there are some key vocabulary terms you
need to know.
Macromolecule
Polymer
Monomer
What do these words mean?
So What Is A
Macromolecule?
A very large molecule, such as a
polymer or protein, consisting of
many smaller structural units linked
together.
Biological
Macromolecule
All biological macro-molecule are
made up of a small number of
elements: Carbon, Hydrogen, Oxygen,
Nitrogen, Phosphorus and Sulfur
Elements of Life

96% of living
organisms is made
of:
 carbon
(C)
 oxygen (O)
 hydrogen (H)
 nitrogen (N)
 phosphorus (P)
Next Word…..
Polygons
Polyester
Polygamy
What does
“Mono” mean?
A Polymer
Here are some analogies to better
understand what polymers and monomers
are….
EXAMPLE of
POLYMER
A TRAIN
A NECKLACE
MONOMER
?
?
If the train is the whole polymer, what would be the small
groups that make up the train? If the necklace is the polymer,
what are the monomers that make up the necklace?
A Polymer
Here are some analogies to better
understand what polymers and monomers
are….
EXAMPLE of
POLYMER
A TRAIN
A NECKLACE
MONOMER
THE CARS
EACH PEARL
If the train is the whole polymer, what would be the small
groups that make up the train? If the necklace is the polymer,
what are the monomers that make up the necklace?
Now you and a buddy
need to think of at least 2 other
analogies for a polymer and its
monomers.
Molecules of Life
Put C, H, O, P, and N together in different
ways to build living organisms
 What are bodies made of?

◦ carbohydrates
 sugars & starches
◦ proteins
◦ fats (lipids)
◦ nucleic acids
 DNA, RNA
Don’t forget water

Water
◦ 65% of your body is H2O
◦ water is inorganic
 doesn’t contain carbon

Rest of you is made of carbon molecules
◦ organic molecules




carbohydrates
proteins
fats
nucleic acids
Keep the following in mind when
studying this material:
Nucleic Acids
What they look like
Carbohydrates
What they do/Where are
they
Lipids
What are they made up ofat the level of atoms
Proteins
Carbohydrates

Function:
◦ quick energy
glucose
C6H12O6
◦ energy storage
◦ structure
 cell wall in plants

Examples
sucrose
◦ sugars
◦ starches
◦ cellulose (cell wall)
starch
Cellulose

Cell walls in plants
◦ herbivores can digest cellulose well
◦ most carnivores cannot digest cellulose
 that’s why they
eat meat
to get their energy
& nutrients
 cellulose = roughage
 stays undigested
 keeps material
moving in your
intestines
Different Diets of Herbivores
Cow
can digest cellulose well;
no need to eat other sugars
Gorilla
can’t digest cellulose well; must add
another sugar source, like fruit to
diet
Helpful bacteria

How can cows digest cellulose so well?
◦ BACTERIA live in their stomachs & help digest
cellulose-rich (grass) meals
CARBOHYDRATES
Carbohydrates are chains
(polymers) made of monomers. The
most common monomer of
carbohydrates is…
The shape of Glucose is a
hexagonal ring
CARBOHYDRATES
Each carbohydrate is made up of…
THINK: “CHO”
Building carbohydrates

Synthesis
1 sugar =
monosaccharide
2 sugars =
disaccharide
|
|
|
glucose
glucose
maltose
BIG carbohydrates

Polysaccharides
◦ large carbohydrates
 starch
 energy storage in plants
 potatoes
 glycogen
 energy storage in animals
 in liver & muscles
 cellulose
 structure in plants
 cell walls
 chitin
 structure in arthropods & fungi
 exoskeleton
Building BIG carbohydrates
glucose + glucose + glucose… = polysaccharide
starch
(plant)
energy
storage
glycogen
(animal)
PROTEINS
They are the major structural molecules in living things
for growth and repair : muscles, ligaments, tendons, bones,
hair, skin, nails…IN FACT ALL CELL MEMBRANES have
protein in them
They make up antibodies in the immune system
They make up enzymes for helping chemical reactions
They makeup non-steriod hormones
Proteins:
Multipurpose molecules
Proteins
Examples
◦ muscle
insulin
◦ skin, hair, fingernails, claws
 collagen, keratin
◦ pepsin
pepsin
 digestive enzyme
in stomach
◦ insulin
 hormone that controls blood sugar
levels
collagen (skin)
Proteins
 Function:
◦ many, many functions
 hormones
 signals from one body system to another
 insulin
 movement
 muscle
 immune system
 protect against germs
 enzymes
 help chemical reactions
Proteins

Building block =
amino acids
amino amino amino amino amino
acid – acid – acid – acid – acid

20 different amino acids
There’s
20 of us…
like 20 different
letters in an
alphabet!
Can make lots of
different
words
HO
H
|||
—N—
—C— C—OH
Hvariable |
group
Amino acid chains

Proteins
◦ amino acids chained into a polymer
amino acid
amino acid
amino acid
amino acid
amino acid
 Each amino acid is different

some “like” water & dissolve in it

some “fear” water & separate from it
Water-fearing amino acids
 Hydrophobic
“water fearing” amino acids
 try to get away from water in cell

the protein folds
Water-loving amino acids
 Hydrophillic
“water loving” amino acids
 try to stay in water in cell

the protein folds
For proteins: SHAPE matters!

Proteins fold & twist into 3-D shape
◦ that’s what happens in the cell!

Different shapes = different jobs
growth
hormone
hemoglobin
pepsin
collagen
It’s SHAPE that matters!
Proteins do their jobs, because
of their shape
 Unfolding a protein destroys its shape

◦ wrong shape = can’t do its job
◦ unfolding proteins = “denature”
 temperature
 pH (acidity)
unfolded
“denatured”
folded
PROTEINS
Each protein is made up of…
THINK: “CHONS”
Lipids

Function:
◦ energy storage
 very concentrated
 twice the energy as carbohydrates!
◦ cell membrane
◦ cushions organs
◦ insulates body
 think whale blubber!
2003-2004
Lipids
 Examples
◦ fats
◦ oils
◦ waxes
◦ hormones
 sex hormones
 testosterone (male)
 estrogen (female)
2003-2004
LIPIDS
Lipids are not polymers. But they
are created by the same process
that creates polymers.
The most common lipids are…
The Shape of a triglyceride is like
the letter
E
This is a triglyceride molecule
Structure of Fat
not a chain (polymer) = just a “big fat molecule”
2003-2004
Saturated fats

Most animal fats
◦ solid at room
temperature

Limit the amount in
your diet
◦ contributes to heart
disease
◦ deposits in arteries
2003-2004
Unsaturated fats

Plant, vegetable & fish fats
◦ liquid at room
temperature
 the fat molecules
don’t stack tightly
together

Better choice in your
diet
2003-2004
Saturated vs. unsaturated
saturated
unsaturated
2003-2004
Other lipids in biology

Cholesterol
◦ good molecule in cell membranes
◦ make hormones from it
 including sex hormones
◦ but too much cholesterol in blood may lead
to heart disease
2003-2004
Other lipids in biology

Cell membranes are made out of lipids
◦ phospholipids
◦ heads are on the outside touching water
 “like” water
◦ tails are on inside away from water
 “scared” of water
◦ forms a barrier
between the cell
& the outside
2003-2004
LIPIDS
Each lipid is made up of…
THINK: “CHOP”
The 4th type of biochemical
macromolecules are the
NUCLEIC ACIDS
The
types of Nucleic Acids
DNA (DeoxyriboNucleic Acid)
RNA (RiboNucleic Acid)
DNA
Nucleic Acids
 Function:
◦ genetic material
 stores information
 genes
 blueprint for building proteins
 DNA  RNA  proteins
 transfers information
 blueprint for new cells
 blueprint for next generation
proteins

DNA
◦ Inside the nucleus of a cell

RNA
◦ Inside the nucleus and in the
cytoplasm


DNA and RNA are polymers of 4 different
nucleotides (monomers)
Each nucleotide is composed of three parts:
◦ a nitrogen base
 DNA: adenine (A), cytosine (C), guanine (G), thymine (T)
 RNA: adenine (A), cytosine (C), guanine (G), uracil (U)
◦ a five-carbon sugar
 Deoxyribose (DNA)
 Ribose (RNA)
◦ a phosphate group
◦
◦
DNA is double-sided
RNA is single-sided
Nucleic acids
sugar
phosphate
N base
DNA and RNA
Think “PHONC”
Building large molecules of life

Chain together smaller molecules
◦ building block molecules = monomers

Big molecules built from little molecules
◦ polymers
Building large organic molecules

Small molecules = building blocks

Bond them together = polymers
Building important polymers
Carbohydrates = built from sugars
sugar – sugar – sugar – sugar – sugar – sugar
Proteins = built from amino acids
amino amino amino amino amino amino
acid – acid – acid – acid – acid – acid
Nucleic acids (DNA) = built from nucleotides
nucleotide – nucleotide – nucleotide – nucleotide
How to build large molecules

Synthesis
◦ building bigger molecules from
smaller molecules
◦ building cells & bodies
 repair
 growth
 reproduction
+
ATP
How to take large molecules apart

Digestion
◦ taking big molecules apart
◦ getting raw materials
 for synthesis & growth
◦ making energy (ATP)
 for synthesis, growth & everyday functions
+
ATP
Example of digestion
ATP
ATP
ATP
ATP
ATP
starch
ATP
glucose
ATP

Starch is digested to glucose
Example of synthesis
amino acids
protein
 Proteins are synthesized by bonding amino acids
amino acids = building block
protein = polymer
Why do we eat?

We eat to take in more of these chemicals
◦ Food for building materials
 to make more of us (cells)
 for growth
 for repair
◦ Food to make energy
 calories
 to make ATP
ATP
What do we need to eat?

Foods to give you more building blocks &
more energy
 for building & running bodies
◦
◦
◦
◦
◦
◦
◦
carbohydrates
proteins
fats
nucleic acids
vitamins
minerals, salts
water