Download Organic Compounds

Organic Compounds
Macromolecules
Elements and Compounds in Living
Things
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90 elements NATURALLY occurring
Only 11 are common in living things
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MOST Common are:
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Carbon
Nitrogen
Oxygen
Hydrogen
These 4 elements make up 96.3% of the human body
20 elements are found in small (TRACE)
amounts in living things
2 Main Groups of Chemical
Compounds
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Organic
Inorganic
Organic Compounds
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Contain carbon
Also tend to be
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Large molecules (made up of lots
of atoms)
Complex
Lots of carbon and hydrogen atoms
bound covalently
These are the primary
compounds that make up the
working structures of living
things!
Inorganic Compounds
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Generally do NOT contain
carbon
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Also tend to be
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CO2 is an exception
Small
Simple
While NOT the major building
blocks of life, they are
absolutely necessary for life
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Think WATER and Carbon
Dioxide!
What’s so special about CARBON?
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It’s a great
Tinker Toy!
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4 outer
(valence)
electrons
Can bind with
4 different
atoms
What’s so special about CARBON?
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Readily forms
COVALENT bonds
with other atoms that
are strong and stable
What’s so special about CARBON?
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Can form chains
of almost
unlimited length
by bonding with
other carbon
atoms
These long
chains can then
FOLD to make
many complex
shapes
THE BOTTOM LINE about CARBON
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It has HUGE potential for making a WIDE
VARIETY of different types of molecules!
How to BUILD (and take apart)
Organic Molecules
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Polymer – a large
molecule made up of
many smaller
subunits
Monomer – a small
subunit (building
block) that can be
joined with other
subunits to make a
polymer
How to BUILD (and take apart)
Organic Molecules
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Polymerization – the process of building
LARGE molecules by joining together
many smaller subunits
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Provides a way for really large complex
molecules to form from smaller ones
Macromolecule – term for VERY large
polymers
How to BUILD (and take apart)
Organic Molecules
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Dehydration
Synthesis
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Process that MAKES
polymers
Two monomers are
joined together by
removing a molecule
of water from
between them
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Dehydration – lose
water
Synthesis – making
or putting together
How to BUILD (and take apart)
Organic Molecules
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Hydrolysis
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Process in which
polymers are broken
apart
Add back the water
that was taken out
Breaks polymer into
monomer subunits
Example: digestion
Bottom Line about Making
Polymers
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Small subunits link together to make large
polymers
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Dehydration reactions link them
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Removal of water
Creates covalent bonds between subunits
To break apart polymers into subunits, you just
add the water back
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Hydrolysis reaction
Breaks covalent bonds between subunits
Bottom Line about Making
Polymers
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Really LONG complex
molecules can be
made and broken
down by these
methods.
Like linking and
unlinking cars in a
train.
FOUR MAJOR GROUPS of Organic
Compounds
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Carbohydrates
Lipids
Proteins
Nucleic Acids
Carbohydrates
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Functions
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Quick ENERGY
They function in short-term energy storage in
plants an animals (ex. Sugar)
They function as intermediate-term storage
(ex. Starch in plants)
They function as structural components in
cells. (ex. Cellulose in cell walls of plants)
GENERAL CARB STRUCTURE:
Monomers and Polymers
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Monomers
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Monosaccharides (single sugars)
Individual car in the train
Polymers
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Polysaccharides
The whole train
Monosaccharides
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Monomers of carbs are
monosaccharides
Simple/single sugars
Basic formula CH2O
Example:
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GLUCOSE; C6H12O6
Sugar made by plants in
photosynthesis
Others: galactose (milk
sugar); fructose (fruit);
Why monosaccharides are
important
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Energy in them can be made QUICKLY
available to living things
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Energy is stored in the chemical bonds of the
sugar molecules
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In particular, bonds between CARBON and
HYDROGEN atoms store lots of energy
When these bonds are broken, energy is
released
This energy is then available to use
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Cellular respiration converts this energy to a
usable form!
Monosaccharide - Glucose
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Note that there are
lots of these C-H
bonds in a sugar
molecule
Each has lots of
potential energy
stored in it
Disaccharides
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DOUBLE sugars
Two monosaccharides
joined
Examples:
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Sucrose (table sugar)
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Glucose + fructose
Lactose (milk)
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Galactose + glucose
Why are Disaccharides useful?
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Not quite so easily
broken down as
monosaccharides
Can by used by plants /
animals for safe
temporary storage of
sugars
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Used in transport in plants
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Sugar not consumed on its
way from leaves to roots
Makes milk harder to
digest in animals
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MOST adult animals cannot
digest milk
Keeps it for YOUNG ONLY
Polysaccharides
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Made by joining MANY monosaccharides
Sugar (thus energy) is STORED in this
form
TYPES of Polysaccharides
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STARCH
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PLANTS store energy in this form
LOTS of GLUCOSE molecules linked in LONG
CHAINS
Animals CANNOT store energy in this form,
but they CAN digest and USE it!
Starch
TYPES of Polysaccharides
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GLYCOGEN
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Energy storage carbohydrate in ANIMALS
Found in the liver, mostly.
ALSO made of lots of glucose linked together
As you consume sugar, your liver converts it
to glycogen and stores it (stores one day’s
worth at a time).
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Through the day as you need energy, the liver
breaks off sugars from the glycogen molecules for
you to use and puts it into your bloodstream.
Polysaccharides - Glycogen
Polysaccharides - Cellulose
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Cellulose
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STRUCTURAL carbohydrate in
PLANTS
ALSO lots of glucose linked
together
CELL WALLS in plant cells
SUPPORT and PROTECTION
UNDIGESTABLE BY ANIMALS
WOOD
Polysaccharides - Chitin
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STRUCTURAL
carbohydrate
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Cell walls of fungi
Exoskeleton of
arthropods
Lipids
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Waxes
Oils
Fats
Steroids
Hormones
All are NONpolar
(don’t dissolve in
water)
Functions of Lipids
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Energy Storage animals (and limited in
plants – seeds)
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Insulation
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Keeps animals warm
blubber
Functions of Lipids
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Waterproofing
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Duck feathers are kept dry
by a layer of oil
Mammal fur (beaver, otter,
etc.), too.
Functions of Lipids
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shock-absorption/
protection of organs
formation of membranes
in cells and organelles
make important
compounds - cholesterol
and hormones (estrogen
and testosterone, for
example) used for
communication
Structure of Lipids
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Glycerol + 3 fatty
acids
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Glycerol is just a
“connector”
3 fatty acids are the
most important part
Why are Fatty Acids the “important
part”?
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fatty acids are LONG
chains of carbon and
hydrogen atoms
remember: bonds
between carbon and
hydrogen atoms STORE
ENERGY!
So fats (with their 3 fatty
acids) are PACKED with
energy and are GREAT at
energy storage
EFFICIENT energy storage
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Because there are SO MANY C-H bonds in
fatty acids, lipids are VERY efficient ways
of storing energy.
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Fats produce 6x more energy per gram
than carbohydrates do!
more efficient means better for animals lots of energy without much "baggage“ for
animals that need to move.
Efficient energy storage
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Some plants do use oils for energy storage
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Corn oil, peanut oil, etc.
Efficiency is just not as important for
plants since they don’t have to move
around - so starch is still often the primary
energy storage molecule for them
Saturated vs. Unsaturated Fats
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saturated fat - when each carbon in a fatty acid
shares a single covalent bond with as many
hydrogen atoms as possible
 causes the fatty acids to be very straight
 fatty acids like this can pack very tightly
together
 because they can pack tightly, saturated fats
tend to be solid at room temperature
 butter and lard
Saturated Fat
Saturated vs. Unsaturated Fats
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unsaturated fat - a fatty acid that has at least two
carbons double bonded to each other instead of to
hydrogen atoms - that is,
 the carbons are NOT bound to the maximum number
of hydrogen atoms.
 causes the fatty acids to bend
 fatty acids like this cannot pack very tightly together
 because of this unsaturated fats tend to be liquid at
room temperature
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oils
Saturated vs. Unsaturated Fats
Protein
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Functions – MANY!
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Structural – build structures in organisms
muscle contraction
communication between cells
movement of cell parts
MOST IMORTANT: ENZYMES!!!
Structure of Proteins
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Monomers of Proteins are
AMINO ACIDS (20 types)
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ALWAYS a carbon in the
middle
ALWAYS an H at the “top”
ALWAYS an amino group
on one side
ALWAYS a carboxyl group
on the other side
R group is always there,
but TYPE of R-group
VARIES
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20 different types
All have different
characteristics
Protein Structure
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A protein is a polymer of amino acids
Amino acid monomers link together by covalent
bonds called PEPTIDE BONDS. = Proteins are
long chains of amino acids
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sometimes called polypeptides in reference to their
peptide bonds.
Peptide bonds are formed the same way as all
bonds among the organic compounds we're
discussing - DEHYDRATION reactions.
Making Proteins from Amino Acids
20
Amino
Acids
Enzymes
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Chemical reactions are what living things are all
about.
Most of the chemical reactions in your body, if
left to themselves, would not happen quickly
enough for you to survive.
CATALYST - something that speeds up a
chemical reaction
Enzymes are proteins that act as catalysts
for the chemical reactions in your body.
Enzymes
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Enzymes have unique
shapes designed to fit the
chemicals that they are to
"speed up" (the
SUBSTRATES of the
REACTION)
The region of the enzyme
that FITS the substrate
specifically is called the
enzyme's ACTIVE SITE.
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The substrate BINDS with the
enzyme at the enzyme's
ACTIVE SITE.
Enzymes
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Enzymes can either:
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bring two (or more) reactants together more
quickly and force them to react
stress bonds in a single substrate and cause it
to break apart more easily
Enzymes
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An enzyme itself is NOT CHANGED by
the chemical reaction it catalyzes
A single enzyme can repeat its catalytic
activity with many, many substrate
molecules - that is, it can be used over
and over again.
Enzyme catalyzed reaction
Enzymes
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ENZYMES ARE VERY SPECIFIC!
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If the shape of the enzyme's active site
becomes damaged, it will be unable to bind
with its substrate
Thus, it will be unable to function.
If an enzyme loses its shape it is said to be
DENATURED.
enzymes can be denatured by HEAT
 or by extremes in pH.
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Nucleic Acids
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Functions
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Main function is information storage.
tells the cell how to function
transmits genetic information to offspring
Examples:
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The main component in DNA, RNA, ATP, & NAD
Nucleic Acids
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Structure
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Monomers of nucleic
acids are nucleotides
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Sugar
Phosphate
Base (ATCG)
Many nucleotides
linked together give a
nucleic acid
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RNA and DNA are the
two main examples
Elements in each Macromolecule
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Carbohydrates
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C, H, O only
Protein
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C, H, O, N
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Lipid
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C, H, O
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N, P in cell membranes
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Some contain S
Nucleic Acids
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C, H, O, N, P
Summary of the Organic
Molecules: