Download Macromolecules 1

Macromolecules
A. Monomers- subunits from which
macromolecules are built:
1. Monosaccharide
2. Amino Acid
3. Nucleic Acid
4. Fatty Acids and Glycerol
B. Polymers-consist of many similar
monomers linked by covalent bonds to
form macromolrcules:
1. Carbohydrates
2. Proteins
3. Lipids
4. Nucleic Acids
C. Condensation- AKA Dehydration
Synthesis- reaction to connect
monomers to build polymers.
1. one monomer provides a hydroxyl
and the other provides a hydrogen to
form H2O, then a covalent bond forms
between the left over atoms.
2. These are anabolic reactionsrequire enzymes, energy, and monomer
building blocks.
____________ . ______________
D. Hydrolysis- covalent bonds in
polymers are broken down by adding
H2O
1. a hydrogen and a hydroxyl group
from a split water molecule attaches
where the covalent bond between
monomers used to be.
2. these are catabolic reactions which
dominate the digestion, and require
energy and enzymes
Carbohydrates
A. Composed of C:H2O ratios
B. Serve as energy sources for
humans and animals
ex. glucose
C. Serve as structural components
for plants
ex. cellulose
D. Simple Sugars:
aka. Monosaccharides
1. most sugars end in –ose
2. have carbonyl and multiple
hydroxyl groups
3. if the carbonyl group is at the
end, the sugar is an aldose; if
not, it is a ketose
ex. Glucose C6H12O6
is an aldose
ex. Fructose C6H12O6
is a ketose
Glucose and Fructose are
structural isomers
4. Classified by the # of Carbons
in the backbone:
ex. Glucose and Fructose are
Hexose s
5. Some monosaccharides are
enantiomers; which have the
same molecular formula but,
differ in the spatial arrangement
about an asymmetrical Carbon
ex. Glucose and Galactose
6. Linear sugars form covalent
rings to increase stability in
aqueous solutions
- OH of C #1 up is the 
- OH of C #1 down is the 
E. Disaccharides- double sugars
1. ex. Sucrose- composed of
fructose and glucose bound by
condensation synthesis aka.
Glycosidic Linkage
F. Polysaccharide- polymers of
monosaccharides
1. energy storage
2. building blocks
3. monomers (usually Glucose)
are joined by 1-4 glycosidic
linkages
4. ex. Cellulose- component of
plant cell walls – is a polymer of
beta 1-4 glycosidic linkages
between glucoses
- linked structures are linear, which
allows H atoms on one strand to form
H-bonds with OH atoms on another
strand  form strong microfibrils
for structure in plants
5. Human enzymes do NOT recognize 
glycosidic linkages and  cannot digest
cellulose
a. cellulose is an insoluble FIBER that
passes through our digestive tract
and scours it clean plus stimulates
the production of mucus to keep it
lubricated.
b. Cellulase enzymes in microbes do
digest cellulose into glucoses
1. eukaryotic herbivores have
Symbiotic relationships with
Cellulolytic microbes that
break down the cellulose for
them
6. Starch is a polysaccharide of  1-4
Glycosidic linkages
a. Amylose- unbranched starch
forms a helix
b. Amylopectin- branched helix
- storage macromolecules in plants
stores Carbon and energy
- animal enzymes recognize the  1-4
Glycosidic bond and can break down
starch when needed for energy or
Carbon to support metabolism
c. Glycogen- Animal Starch, branched
for storage in animals
7. Chitin- structural polysaccharide
a. exoskeleton of arthropods
b. cell walls of Fungi
c. contains Nitrogen
d. similar to cellulose in structure
Lipids
Hydrophobic Substances
(structure are held together by
non-polar, covalent bonds)
A. Fats- long-term energy storage
in animals and Humans
1. adipose tissue- stores fat
2. 9 calories per gram
3. insulation- fats do not
conduct heat  homeostasis
4. cushion vital organs
5. Triglycerides: composed of 3
fatty acids joined to one
glycerol through dehydration
synthesis (condensation)
a. Fatty acids composed of
a long hydrocarbon
skeleton that are
Hydrophobic, attached
to one carboxyl group
(COOH)
1.fatty acids may vary in
length ie. # of Carbons
2. fatty acids may vary in the
# and location of C=C
a. saturated fatty acids1. have NO C=C.
2. saturated with H
3. yield more calories
4. solid at room temp.
5. animal fats
a diet rich in
saturated fats
contributes to
atherosclerosis,
hardening of the
arteries through
plaque deposit.
b. unsaturated fatty
acids1. Have C=C
-kinks at double bonds prevent tight
packing
2. Liquid at room temp.
3. Plant & fish oil
4.Yield less cal.
-One double
bond yield less
energy than two
single bonds
b. Glycerolcomposed of a three Carbon
skeleton with a hydroxyl attached
to each
1. one glycerol and three fatty
acids combine through a type of
condensation (dehydration
synthesis) that results in ester
bonds yielding a triglycerol
__________
.
_________
- all triglycerides are hydrophobic
B. Phospholipids- composed a
glycerol attached to two fatty acids
and a phosphate group, which may
have additional groups attached to it.
1. Amphipathic molecule –
a molecule that has both a
polar and a non-polar
region
a. polar head PO4=
hydrophilic
b. non-polar tail (fatty acids)
hydrophobic
2. Micelle- structure that forms
when an amphipathic
molecules combines with
H2O.
a. hydrophilic heads on the
outside (in contact with
water)
b. hydrophobic tails on the
inside (out of the reach
of water)
3. Cellular membranescomposed of phospholipid
bilayers.
a. two layers of
phospholipids with the
heads facing the extra and
intra cellular aqueous
fluids and the tails facing
each other.
C. SteroidsLipid compounds with Carbon
skeletons consisting of fused rings
with functional groups attached.
1. Cholesterola. precursor from which all
steroids are synthesized
b. HDL- high density
lipoproteins are the “good”
cholesterol.
-Reduces cholesterol
deposition in arteries
-exercise increases HDL
-HDL levels should be
45 mg/dl and above
c. LDL- low density lipoprotein
is the ‘bad’ cholesterol.
-increases the deposition
of cholesterol inside
arteries:
-atherosclerosisnarrowing of arteries
-arteriosclerosishardening of arteries
-hypertensionelevated blood pressure
above 120/80
-LDL levela should be
below 130
2. Hormones:
Estrogen, Testosterone
Proteins
Polypeptides are polymers of
amino acids connected in
specific sequences
A. Function-depends on
conformation
1. Structural macromolecules:
muscle, collagen, bone
2. Storage of a.a. ex. Casein
3. Transport- ex. HDL/LDL
4. Hormones- Insulin
5. Cell membrane components
6. Antibodies
7. Enzymes
B. polypeptides are polymers of
Amino Acids (20) connected in
a specific sequence (determined
by the genetic code)
synthesized in the Ribosome
with resources such as, mRNA
tRNA, ATP, and enzymes.
C. Amino Acids:
H

H2N  C  COOH

R20
-The physical and chemical
characteristics of the R group
determine the unique characteristics
of a particular amino acid
1. Hydrophobic amino acids:
Have non-polar R groups
2. Hydrophilic Amino Acids
Have polar R groups
3. Ionizing Amino Acids
Have acid or basic R groups
Which ionize at cellular pH
D. Nutritional Sources of a.a.
meat, poultry, fish, dairy, nuts,
legumes, soy, eggs
1. Essential a.a.
Out of the 20 a.a. 8 are
needed in the diet, since the
body does not make them
Tryptophan
Methionine
Valine
Threonine
Phenylalanine
Leucine
Isoleucine
Lysine
2. Non-Essential not required in
diet since the body
synthesizes them
E. Peptide Bond- type of bond that
unites amino acids.
1. dehydration synthesis
condensation occurs with the
removal of an OH group from
the COOH end of one a.a.
and a H from the NH2 of
another a.a.
a. water if formed and
b. a covalent bond forms
between the two a.a.