Macromolecules
1
Organic Compounds
• Compounds that contain CARBON
are called organic.
• Macromolecules are large organic
molecules.
2
Carbon (C)
• Carbon has 4 electrons in outer
shell.
• Carbon can form covalent bonds
with as many as 4 other atoms
(elements).
• Usually with C, H, O or N.
– Example:
CH4(methane)
3
The Atoms of Life
The most frequently found atoms in the body
are “CHNOPS” (not in this order).
Carbon (C)
Hydrogen (H)
What are other
Nitrogen (N)
elements you
Oxygen (O)
expected to be on
Phosphorous (P)
this list?
Sulfur (S)
4
Making the Molecules of
Life
Each molecule has one or more
roles in living systems.
Energy
Structure
Information
5
Macromolecules
• Large organic molecules.
– Also called POLYMERS.
– Made up of smaller “building blocks”
called MONOMERS.
• Examples:
1. Carbohydrates
2. Lipids
3. Proteins
4. Nucleic acids (DNA and RNA)
6
Carbohydrates
7
Carbohydrates
• Small sugar molecules to large sugar
molecules.
• Types:
A. monosaccharide = 1 sugar unit
B. disaccharide = 2 sugar units
C. polysaccharide = many sugar
units
8
Carbohydrates
MONOMER = Monosaccharide: one
sugar unit
• Elements involved: CHO
• Also called “simple sugars”
Examples:
glucose (C6H12O6)
deoxyribose
ribose
fructose
galactose
glucose
9
Carbohydrates
Disaccharide: two sugar unit
Examples:
– Sucrose (glucose+fructose)
– Lactose (glucose+galactose)
– Maltose (glucose+glucose)
glucose
glucose
10
Carbohydrates
Polysaccharide: many sugar units
Called “complex sugars”
Examples:
starch (bread, potatoes)
glycogen (beef muscle)
cellulose (lettuce, corn)
glucose
glucose
glucose
glucose
cellulose
glucose
glucose
glucose
glucose
11
Carbohydrates
3 Functions of carbohydrates:
1. Short term energy storage
for plants & animals
2. Source of carbon
3. Structural elements of cells
and tissues
12
Review Questions
1. What is the difference between a
mono-, di-, and polysaccharide?
2. Provide an example of a mono-,
di-, and polysaccharide.
3. What are 2 functions of
carbohydrates?
13
Polymerization Simulation
• Take the H- from one glucose
molecule and –OH from another
• This creates a water molecule, thus
the reaction is called dehydration
• When we break these bonds
(metabolize our food), it requires
water and is called hydrolysis
• Another reason to stay hydrated!
•
http://bioweb.wku.edu/courses/biol115/wyatt/
biochem/carbos.htm
14
Important Monosaccharides
Glucose:
The basic carbohydrate monomer (C6H12O6)
Instant / immediate energy source
Main energy transport molecule & source for
metabolism
All digested carbohydrates broken down to
this for absorption in the small intestine.
Only fuel used by the brain/nervous tissue
glucose
15
Polysaccharides
Energy source once all
monosaccharides are used (still shortterm energy) IF it can be digested
Three types:
Glycogen
Starch
Cellulose
16
Polysaccharides
Glycogen: storage form of glucose in muscle and
liver
Quickly broken down to produce blood glucose;
used as an energy source once glucose is used
up
17
Starch vs. Cellulose vs. Glycogen
18
Polysaccharides
Cellulose: plant structural form
Different bond between glucose units
We don’t have the enzyme to break that
particular bond, but cows do.
This is “fiber” (aka “roughage”) in our
food.
Ruminants (cows, sheep) DO have the
enzymes to break that bond, so they
can turn it into usable energy
19
Starch vs. Cellulose
20
Type
of
Carb
Example
Structure
Use
Explanation
Glucose
Glycogen
Starch
Cellulose
21
Lipids
22
Lipids
• General term for compounds which are NOT
soluble in water.
• Lipids are soluble in hydrophobic solvents.
– Hydrophobic = hates water
• Remember: “stores the most energy”
• Examples:
1. Fats
2. Phospholipids
3. Oils
4. Waxes
5. Steroid hormones
6. Triglycerides
23
Lipids
The MONOMER for lipids…
*fatty acid chains: Made of C, H, O
3 fatty acids & 1 glycerol make a
triglyceride…
24
Lipids
Triglycerides:
composed of 1 glycerol and 3 fatty acid chains
(monomers).
Elements involved: CHO
H
O
H-C----O C-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH3
O
H-C----O C-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH3
O
fatty acids
H-C----O C-CH -CH -CH -CH
2
2
2
H
glycerol
25
Fatty Acids
There are two TYPES of fatty acids
1. Saturated fatty acids: no double bonds
(maximum # of hydrogens)
(Straight Chain)
saturated
O
C-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH3
2. Unsaturated fatty acids: double bonds
(less than the maximum # of hydrogens)
O
(Bent Chain) unsaturated C-CH2-CH2-CH2-CH
26
Lipids
4 functions of lipids:
1. Long term energy storage
2. Protection against heat loss
(insulation), physical shock & water
loss
3. Chemical messengers (hormones)
4. Major component of membranes
(phospholipids)
27
Review Questions
1. What are the parts of a
triglyceride?
2. What is the difference between a
saturated and unsaturated fat?
3. What are 2 functions of lipids?
28
Proteins
29
Proteins (Polypeptides)
• MONOMER = Amino acids (A.A.s)
• Elements involved: CHON
• Made up of C, H, O and N (amino refers to
the presence of nitrogen)
• There are 20 different amino acids
• A.A.s are bonded together by peptide
bonds to create a…
• Polypeptide: strand of amino acids, which
becomes a protein!
30
Amino Acids
Phenylalanine
(Phe)
Leucine (Leu)
Isoleucine (Ile)
Valine (Val)
Serine (Ser)
Proline (Pro)
Threonine (Thr)
Alanine (Ala)
Tryosine (Tyr)
Histidine (His)
Glutamine (Gln)
Asparagine (Asn)
Lysine (Lys)
Glutamic Acid (Glu)
Aspartic Acid (Asp)
Cystenine (Cys)
Tryptophan (Trp)
Argenine (Arg)
Glycine (Gly)
Methionine (Met)
Start codon
Proteins
Proteins (Polypeptides)
6 functions of proteins:
Examples:
1.
2.
3.
4.
5.
6.
albumin (egg white)
hemoglobin
hormones
muscles
membranes, hair, nails
Enzymes
Storage:
Transport:
Regulatory:
Movement:
Structural:
Cellular reactions:
33
Review Questions
1. What are the monomers that
make up a protein?
2. How are those monomers held
together?
3. What are 2 functions of proteins?
34
Nucleic
Acids
35
Nucleic acids
• Two types:
a. DNA (DeoxyriboNucleic Acid)
- double helix
b. RNA (RiboNucleic Acid)
- single strand
• Nucleic acids are composed of long
chains of nucleotides
36
Nucleic acids
• MONOMER = Nucleotide
• Elements involved: CHONP
• Nucleotides include:
– phosphate group (1 P & 4 Os)
– pentose sugar (5 Cs)
– nitrogen bases:
• ATGC in DNA
• AUGC in RNA
adenine (A)
cytosine (C)
guanine (G)
thymine (T) DNA only
uracil (U) RNA only
37
Nucleotide
Phosphate
Group
O
O=P-O
O
5
CH2
O
N
C1
C4
Nitrogenous base
5-C Sugar
C3
C2
38
5
DNA
double
helix
O
3
3
O
P
5
O
C
G
1
P
5
3
2
4
4
2
3
1
P
T
5
A
P
3
O
O
P
5
O
3
5
P
39
DNA - double helix
40
Nucleic acids
• 5 Functions:
1. Store genetic information
2. Pass genetic information from one
generation to the next
3. Create proteins
4. Determine the job of every cell in
an organism
5. Identify individual organisms
41
Nucleic acids
• Examples:
a. DNA
b. tRNA
c. mRNA
b. rRNA
42
Review Questions
1. What are the parts of a
nucleotide?
2. What is the difference between
RNA & DNA?
3. What are 2 functions of nucleic
acids?
43
Review
1.
2.
3.
4.
What is the main example of
monosaccharides?
What are 3 examples of polysaccharides?
What is the purpose of each one in
humans?
How are monosaccharides used
differently in humans than
polysaccharides? How are they
structurally different from each other?
List, in order, the types of
macromolecules by their effectiveness of
energy usage? (What does our body use
first, second, etc?)
44
Review
5. Draw one molecule of water, labeling the
more positive and more negative regions.
6. Draw 3 water molecules. Label the forces
that a) hold the atoms together and b) the
forces that hold the molecules together
7. How could you break each of the forces from
#6?
8. How is cellulose used differently in plants vs.
cows vs. humans?
45
Part 1: Testing Known Solutions
Test
Molecule it
tests for
Color Before
Color After
IF molecule
is present
Benedict’s
Biuret’s
Iodine
Paper Bag
46