Transcript Structure and Function of Macromolecules

Structure and Function
of Macromolecules
Four Main Types of
Macromolecules
 Macromolecules
are constructed of
smaller units repeating units called
monomers
 Carbohydrates
 Lipids
 Proteins
 Nucleic Acids
Making and breaking of
polymers:

1. Making polymers

Dehydration Synthesis


Losing a water molecule to join two monomers together.
Anabolic reaction


Building polymers
2. Breaking Polymers

Hydrolysis

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Water molecules break polymers apart.
Catabolic reaction

Breaking down polymers
Carbohydrates
 monomer
 monosaccharides
 known

 All
as simple sugars
Disaccharide
have a ratio of 1:2:1 ratio of C:O:H
 CH2O
Monosaccharides:


Examples:
pentose sugars.

5 carbons.
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hexose sugars
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6 carbons
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Ribose
Deoxyribose
Ribulose
Glucose,
Galactose
Fructose.
Typically ring shaped in
aqueous environments like the
cell.
Disaccharides: These are double
sugars with the formula C11H22O11

Polysaccharides
 The
basic formula is ( C6H10O5)n .
These are macromolecules capable
of acting as structural or storage
molecules.
Polysaccharides
 Composed
of repeating glucose
molecules.
 Storage
 Starch
Found in plants roots
 Bulky molecule

 Glycogen
Found in liver of animals
 More compact

Structural Polysaccharides
 Cellulose
 Found
in plant walls
 Cannot be digested by animals
 Chitin
 Only
carbohydrate containing nitrogen.
 Found in insect shells
Structural Polysaccharides:
 Fats

are composed of:
Glycerol

3
3 carbon alcohol
fatty acid molecules
Saturated Verses Non-Saturated
Saturated or Unsaturated?

Saturated fatty acids

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Single bond between carbons.
Found in animals
Typically solids at room temperature: Lard, butter
Unsaturated fatty acids
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Contain one or more double bonds between the carbons.
Double reduces the number of hydrogens that that can be
attached to the carbon in the molecule.
This causes the molecule to bend or kink at each of the
double bond sites.
Found in plants
Typically liquids at room temperature: vegetable oil
Saturated vs UnSaturated Lipids
• Lipids: A group of polymers that have
one characteristic in common, they do
not mix with water. They are
hydrophobic. Some important groups
are fats, phospholipids, and steroids.
•
Lipids
 Provide
insulation
 Serves as an energy storage source
1g.=9 Kcal of energy
 Shock absorber for internal organs.
 Steroids and sex hormones are made
from fats.
Phospholipids:
 Structurally
related to fats but contain 2
fatty acids and one molecule of
phosphate.
 These molecules are found making up
the plasma membrane of cells.
 Amphipathic
 They
exhibit a polar and non polar quality.
 The phosphate group is hydrophilic while
the fatty acid area is hydrophobic.
Steroids:
 Lipids
characterized by a carbon
skeleton of 4 fused rings.
 Cholesterol is an important steroid
found in all animal tissue.
 Plants
do not contain cholesterol.
 Cholesterol is a precursor to steroids
 Cholesterol adds fluidity to membranes.

Animals that live in cold climates have more
cholesterol and unsaturated fatty acids in their
membranes
Cholesterol
Proteins:
 macromolecules
that make up 50% of
the dry weight of most cells.
Types of proteins:

1. Structural ( support)
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2. Storage food source, examples:
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examples: actin and myosin
6. Antibodies defense,
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example insulin,
5. Contractile movement,
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examples: hemoglobin and cell membrane proteins
Hormonal coordinates bodily activities,
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
ovalbumin and casein
3. Transport moves other substances,
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examples: elastin, collagen, and keratin
examples: Ig.E, IgA, and Ig.G 7.
Enzymes aid in chemical reactions,

examples: amylase and proteases
Amino Acids:
 Most
amino acids consist of an
asymmetrical carbon bonded to an,
amino group, hydrogen, an R group,and
a carboxyl group.
Amino Acids:

Most amino acids
consist of an
asymmetrical
carbon bonded to
an, amino group,
hydrogen, an R
group,and a
carboxyl group.
Protein conformation:
 refers
to the three dimensional shape of
a protein molecule. This shape is
important to its function. If the
conformation is changed, even slightly ,
then the function of the protein
changes.
Nucleic Acids
( DNA and RNA)

Nucleotides:
monomers that come
together to form a
nucleic acid. They
contain either a ribose
or deoxyribose sugar (
ribose has one more
oxygen in its molecule),
a phosphate and a
nitrogen base
DNA Base pairing rules.
DNA