Transcript The Chemical Building Blocks of Life

The Chemical Building Blocks
of Life
Chapter 3
Why Carbon
• Carbon is the main building molecule of all
things on earth because it is able to bond
up to 4 different molecules or compounds
Prefixes
• Chemicals named based on number of carbons and
types of bonds.
Macromolecules are complex
assemblies of molecules
Polymers: long molecular built by
linking together smaller units.
How do we break bonds?
Functions of Proteins
Function
Class
Examples
Enzyme Catalysis
Enzymes
Proteases
Defense
Cell surface
antigens
Antibodies
Transport
Circulating
transporters +
membrane
transporters
Hemoglobin,myogl
obin
NA/K Pump
Support
Fibers
Collagen, elastin
Motion
Muscle
Myosin, Actin
Regulation
Hormones
Insulin
Storage
Ion Binding
Ferritin
Amino Acids: The building blocks of
proteins
Each Amino Acids Properties are
Determined by it’s side group
• 1. Nonpolar amino acids have R groups that
contain CH2 or CH3
• 2. Polar uncharged AA’s have R goups that
contain oxygen or only H
• 3. Charged AA’s have R goups that contain
acids or bases ex HCL or NAOH
• 4. Aromatic AA’s have R groups that contain an
organic carbon ring
• 5. Special Function AA’s Methionin- start codon
proline- causes kinks, cysteine links chains
together.
How to AA’s Make Proteins?
• They bind via peptide bonds forming
polypeptides
Notice the Different Motifs of
Secondary structure
Four Levels of Protein Structure
5 types of bonds that contribute to
protein shape
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•
•
•
•
1. Hydrogen bonds- O-H
2. Disulfide Bridges S-S
3. Ionic Bonds- Based on Chare
4. Vanderwalls- weak attraction
5. Hydrophobic interactions
Chaperone proteins also help in
protein folding
How Proteins Unfold
• When bonds are broken proteins will
unfold
– Caused by:
» High Temperature
» Change in pH
» Enzymes my cause denaturatuin
• Denaturation vs Dissacociaion- not the
same thing!
Nucleic acids store and transfer
genetic information
• DNA- deoxyribonucleic acid stores genetic
info
• RNA- ribonucleic acid important in
transcription
– 3 main differences
• DNA is double stranded while RNA is single
stranded
• DNA has deoxyribose as the sugar whereas RNA
has ribose
• RNA has the nucleotide Uracil in place of Thymine
Structure of DNA
• Double stranded
• Has sugar phosphate
backbone
• Nucleotides are
bonded with hydrogen
bonds
• Double bond C-G,
Single A-T
Purines and Pyrimidines
What came first?
• DNA is thought to have
evolved from RNA in
order to protect and
preserve genetic
information
Lipids Make Membranes and Store
Energy
• Good for long term
energy storage.
• Hydrophobic/hydrophi
lic interactions make
bilipid layered
membrane
Good Fats vs Bad Fats
• Saturated- has max number of possible
Hydrogen atoms- no double bonds ex
butter
• Unsaturated- has double bonds ex veggie
oil
• Polyunsaturated- has more than one
double bond
Carbohydrates: Short term energy
storage and building materials
• General Formula for a carbohydrate is CH2O
• Monosacharides- simple sugars ex, glucose,
fructose, galactose, ribose, deoxyribose
• Disacharides- 2 monosacharides joined by a
covalent bond- dex maltose ( glucose+glucose)
• Polysacharides- more than 2 monosacharides
joined together.
Sugar Isomers
• An isomer has the same empirical formula but different
structural forms.
Transport
• Most of the sugar we eat are disacharides.
Why?
• This allows for better transport
• Less of the important monosacharide is
lost in transport when it is joined to
another sugar. In our case we get the most
glucose possible when it is paired with
another sugar.
Storage Polysacharides
• Plants store energy in starches
• Animals store energy in glycogen
Structural Carbohydrates
• Cellulose- found in the cell walls of plants
• Chitin- found in the shells of many
arthropods
• These types of carbohydrates are not
easily digested.