Download Chemistry: Macromolecules

Macromolecules
Building Complex Molecules
That Comprise Living Things
Comparison of Terms
Molecule
Two or more atoms joined by
chemical bonds
Macromolecule Large polymer made of
repeating monomer units
Four types of organic macromolecules
are important in living systems.
Macromolecules: Polymers
Made of Repeating Monomers
Macromolecule Monomer Unit
Carbohydrates
Sugars
Lipids
Proteins
Fatty acids
Nucleic Acids
Nucleotides
Amino acids
Organic Macromolecules
Contain Carbon
Question: How many
electrons does carbon need
to fill its outer energy level?
double
bond
Carbon atoms can be joined
by single, double or triple
bonds.
triple
bond
Synthesis and Breakdown of
Macromolecules
Dehydration
Synthesis
Hydrolysis
Removal of water to add
monomer units
Addition of OH and H
groups of water to break
a bond between
monomers
Dehydration Synthesis / Hydrolysis
Dehydration Synthesis
Hydrolysis
Carbohydrates: Structure
• Simple
– Monosaccharides= one sugar unit
Glucose = blood sugar
All cells use glucose for energy
Chemical Formula for a Six-Carbon Sugar
Carbohydrates: Structure
• Simple
– Disaccharides = two sugar units
CH2OH
HOCH2 O H
O
H
H
+
H
H HO
OH H
CH2OH
HO
OH HO
HO
H
H HO
Glucose + Fructose
CH2OH
H
HOCH2
O
O
H
H
H HO
H
OH H
O
HO
CH2OH
H
H HO HOH HO
Sucrose & Water
Carbohydrates: Structure
• Simple
– Disaccharides = two sugar units
• Sucrose = glucose + fructose
table sugar
• Lactose = glucose + galactose
milk sugar
• Maltose = glucose + glucose
seed sugar
Carbohydrates: Structure
• Complex
– Polysaccharides= many sugar units
• Starch -- storage in plants
• Glycogen -- storage in animals
• Cellulose -- plant cell walls, indigestible (fiber)
Carbohydrates: Functions
• Energy source
• Structural component
• Cell-cell communication
Mac ‘n Cheese Nutrition Label
Nutrition Facts
Serving Size 1 cup (228g)
Servings Per Container 2
Start here
Amount Per Serving
Calories 250
Limit these
nutrients
Get enough
of these
nutrients
Total Fat 12g
Saturated Fat 3g
Trans Fat 1.5g
Cholesterol 30mg
Sodium 470mg
Total Carbohydrate 31g
Dietary Fiber 0g
Sugars 5g
Protein 5g
Vitamin A
Vitamin C
Calcium
Iron
Calories from Fat 110
% Daily Value
18%
15%
10%
20%
10%
0%
4%
2%
20%
4%
Lipids: Structure
• Triglyceride—predominant form in diet
– One molecule of glycerol
– Three fatty acids
Lipids: Structure
• Types of Fatty Acids
– Saturated – 2H per internal carbon
– Unsaturated -- <2H per internal carbon
one or more double bonds
• Monounsaturated – one double bond
• Polyunsaturated – more than one double bond
Triglyceride
Formation
H
Glycerol
Remove
These
Waters
Add 3
Fatty
Acids
HC
OH
OH
C O
HCH
HCH
HCH
H
H
Triglyceride
H
C
CH
OH
OH
OH
OH
C O C O
HCH HCH
HCH HCH
HCH HCH
H
H
H
H
H
HC
O
C O
HCH
C O
HCH
HCH
HCH
HCH
H
HCH
H
HOH
C
O
C O
HCH
C O
HCH
HCH
HCH
HCH
H
HCH
H
HOH
CH
O
C O
HCH
C O
HCH
HCH
HCH
HCH
H
HCH
H
HOH
3 Waters
Emulsification
• Physical dispersion of lipids
– Mixing with a molecule having a polar
and non-polar end
– Bile from gall bladder emulsifies fats
prior to digestion
Lipids: Structure
•Phospholipid—component of cell membranes
Polar
Head
Glycerol
Hydrophilic
Fatty Acid Tails
Hydrophobic
Lipids: Structure
• Steroids
– Linked carbon rings
– Natural body components
• Hormones
• Cholesterol
Steroids
Cholesterol
Estradiol
Testosterone
Lipids: Functions
• Concentrated energy source
• Structural components of cell
membranes
– Phospholipids
– Cholesterol
• Communication
– Steroid Hormones
• Protection from water
– Waxes
Cholesterol
Phospholipids
Mac ‘n Cheese Nutrition Label
Nutrition Facts
Serving Size 1 cup (228g)
Servings Per Container 2
Start here
Amount Per Serving
Calories 250
Limit these
nutrients
Get enough
of these
nutrients
Total Fat 12g
Saturated Fat 3g
Trans Fat 1.5g
Cholesterol 30mg
Sodium 470mg
Total Carbohydrate 31g
Dietary Fiber 0g
Sugars 5g
Protein 5g
Vitamin A
Vitamin C
Calcium
Iron
Calories from Fat 110
% Daily Value
18%
15%
10%
20%
10%
0%
4%
2%
20%
4%
Proteins: Structure
• Primary structure = chain of amino acids
– Amino acids have common features
Carboxylic Acid
Group
Amino
Group
R
Central
Carbon
The “R” Group
Differs for Each Amino Acid
Proteins: Structure
Forming the Protein Chain
Phenylalanine
Leucine
Dehydration Synthesis
between COOH & NH2
Proteins: Structure
Forming the Protein Chain
The Peptide Bond
Water
Phenylalanine-Leucine Dipeptide
Four Levels of Protein Structure
Primary
(Sequence)
Tertiary
(Folding by
R-group
interactions)
Quaternary
(Two or more chains
associating)
Secondary
(Coiling by
Hydrogen Bonding)
Four Levels of Protein Structure
Primary Structure = sequence of amino acids in chain
Four Levels of Protein Structure
• Secondary Structure
Folded structure due to hydrogen bonds
between the amino and acid groups of amino
acids
N
C
H
O
O
C
N
C
H
O
H
O
H
N
C
N
or
Found in most proteins
Found in silk
Four Levels of Protein Structure
• Tertiary Structure:
Three dimensional folded structure due to
attractions and repulsions between R groups
Can involve
covalent bonding
hydrogen bonding
ionic interactions
hydrophilic and hydrophobic interactions
Hair Curling
S
|
S
|
|
|
S
|
S
|
S
|
|
S
Straight
Hair
|
S
|
S
S
|
S
|
|
|
|
Naturally
Curly
Hair
Four Levels of Protein Structure
• Quaternary Structure:
Association of two or more protein
chains
eg. Hemoglobin is composed
of 4 protein chains
2 are called alpha
hemoglobin
2 are called beta
hemoglobin
Denaturation of Proteins
• Disruption of secondary, tertiary or
quaternary protein structure
• Caused by heat or changes in pH
• Irreversible, causes loss of protein
function
protein unfolds
Proteins: Functions
• Structural Component of Cells
• Control of Metabolic Reactions: enzymes
• Maintain homeostasis
– Transport substances in blood
– Antibodies protect against
invaders
• Growth and Repair
• Support and Motion
• Communication
– Protein Hormones
– Cell Receptors
• Energy source
Protein
Protein