Macromolecules
Life: Small Picture to Big Picture
Macromolecules
What are Macromolecules?
• Cells and their organelles are made up of
smaller building blocks called
macromolecules.
• There are 4 basic types of
macromolecules. They are:
– Lipids
– Proteins
– Carbohydrates
– Nucleic Acids
Monomers & Polymers
• Macromolecules are actually made up of
even smaller subunits. Each subunit of a
macromolecule is called a monomer.
• The macromolecules themselves are
called polymers, because they are made
up of many of these subunits.
Monomer: one basic unit or subunit
Polymer: a chain of many basic units
Macromolecules
• Large organic molecules.
• Also called POLYMERS.
• Made up of smaller “building blocks” called
MONOMERS.
• Monomers combine to form polymers
through a process called
POLYMERIZATION
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How are Macromolecules
Formed?: Dehydration Synthesis
• Also called “condensation reaction”
• Forms polymers by combining
monomers by “removing water”.
HO
H
HO
H
H2O
HO
H
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How are Macromolecules
Separated or Digested?
Hydrolysis
• Separates monomers by “adding
water”
HO
H
H2O
HO
H
HO
H
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What you need to know:
• Names of the 4 macromolecules
• Structure- monomers and polymers of
each
• Function- what are they used for?
• Food sources- what foods will you find
these in?
• Indicator Tests- what tests do we use to
find out if a food contains them?
Lipids
Lipids: Structure
• Lipids are made up of…
– Monomer (basic unit): fatty acids
– Polymer (chain of units): lipids
• Specific examples: triglycerides, phospholipids
Lipids: Structure*
Properties of Lipids
caused by:
• Saturated vs.
Unsaturated fatty
acids
• Polar head and
nonpolar tail regions
– Hydrophilic and
hydrophobic regions
Lipids: Function
• Make up the cell membrane, providing cell
structure
• Provide insulation (fat keeps body warm)
• Long-term energy storage
Lipids: Food Sources
• As you might have guessed, fatty foods
contain lipids.
• Lipids are found in meat and fish, oils,
avacados, eggs & nuts.
Lipids: Indicator Test
• Paper Bag Test:
– Smear substance onto paper bag
– If see-thru, it contains lipids
Proteins
Proteins: Structure
• Proteins are made up of…
– Monomer (basic unit):
amino acids
• 20 different kinds!*
– Polymer (chain of units): protein
• More specifically- polypeptides
dipeptide
Amino acids
linked by
peptide
bonds
Proteins: Structure*
20 Amino
Acids:
Some of these
are polar &
hydrophilic,
others are nonpolar and
hydrophobic.
Proteins can
contain both
kinds.
Proteins: Structure
• Proteins have complex
structures. The shape
of a protein determines
its function!
• The levels of protein
structure are:
– Primary structure:
polypeptide chain
– Secondary structure:
polypeptides in coils or
sheets
– Tertiary structure: coils or
sheets form a tangle
– Quaternary structure:
more than one tangle
combine to make a very
complex protein!
Proteins: Function
• Build and repair muscle
and tissues
– “No pain, no gain!”
• Enzymes- proteins that speed up chemical
reactions
Proteins: Food Sources
• Proteins are found in meat, fish,
legumes, nuts, milk, eggs, grains and
soy products.
• There are 6 amino acids that our bodies
cannot make- we can only get these from
food.
Proteins: Indicator Test
• Biuret’s Solution:
– Turns from blue to purple if protein is present
Carbohydrates
Carbohydrates: Structure
• Carbohydrates are made up of…
– Monomer (basic unit): simple sugars (or
monosaccharides)
• Ex.: glucose
– Polymer (chain of units): complex
carbohydrates (or polysaccharides)
• Ex.: starch, cellulose, chitin, glycogen
Disaccharide:
2 simple
sugars bonded
together
Carbohydrates: Function
• Provide body with energy!
Complex carb (ex. Starch)
– What should you eat before
playing the big game?
Candy bar or pasta?
• Candy bar: contains
simple sugars, provides a
short burst of energy
• Pasta: contains starch
which takes longer to
break down, provides
longer-lasting energy
– *We can’t digest celluloseit is used as fiber, or
roughage instead.
Broken down to
disaccharides
Broken down further
• Ex. : corn
Simple sugars (ex. Glucose)
Carbohydrates: Food Sources
• Simple carbs (simple
sugars) are found in
most candy and
sweet drinks, fruit,
vegetables, and milk.
They are quickly
digested and give a
short burst of energy.
• Complex carbs (like
starches) are found in
pasta, bread,
potatoes, legumes &
corn. They take
longer to digest, and
provide energy
longer.
Carbohydrates: Indicator Tests
• Simple Sugars:
– Benedict’s solution
– Blue solution turns
orange/green/brown
• Complex Carbs:
– Lugol’s
solution/Iodine
– Turns from orangered-brown to blackpurple
Nucleic Acids
Nucleic Acids: Structure
• Nucleic Acids are made up of…
– Monomers (basic unit): nucleotides
– Polymers (chain of units): DNA or RNA
Nucleic Acids: Function
• Stores and carries genetic information
Nucleic Acids: Food Sources
• We get nucleic acid components from
vitamins and minerals in our diet.
These in turn, come from fruits,
vegetables, grains, meats, & almost
anything else you can think of with
some nutritional value (no junk food!).
Nucleic Acids: Indicator Test
• You will not be using an
indicator test for these but in
case you’re wondering…
• Dische diphenylamine test
– Turns from clear-light blue
to dark blue if nucleic acids
are present
Digestion & Reconstruction
• When macromolecules are eaten, they are
digested and broken down into their
subunits (monomers).
– Analogy: taking apart an old brick building
• Inside the cells, these subunits are
reconstructed into the macromolecules we
need.
– Analogy: using bricks to build a new building
Digestion Products
Macromolecule
eaten:
Carbohydrates
Broken down in stomach
to:
Simple sugars (i.e. glucose)
Lipids
Proteins
Fatty acids & glycerol
(glycerol further broken
down to glucose)
Amino acids
Nucleic Acids
Nucleotides
Homework
Read Chapter 2.3 (p. 44 - 48) and create flashcards for the
following terms. Some terms may be found in the Elements and
Macromolecules Coloring W.S. or this lecture’s PowerPoint.
1. Monomer
9. Nucleotide
17. Substrate
2. Polymer
10. Ribonucleic Acid (RNA) 18. Active Site
3. Carbohydrate
11. Hydrolysis
19. Catalyst
4. Monosaccharide 12. Protein
20. Peptide Bond
5. Disaccharide
13. Amino Acid
21. Enzymes
6. Polysaccharide 14. Macromolecule
22. Saturated Fats
7. Lipid
15. Lugol’s Solution (Iodine) 23. Unsaturated Fats
8.
Benedict’s
Solution
16. Biuret’s Solution
24. Deoxyribonucleic
Acid (DNA)
25. Polymerization