Download Organic Compounds - Ms. Nevel's Biology Website

Organic Compounds
Necessities for Life
Special Chemicals
of Life
What is an organic compound?
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In Biology, the word organic means “relating
to organisms” NOT food grown without the
use of pesticides, antibiotics, or other
industrial chemicals.
All organic compounds contain covalently
bound carbon & hydrogen.
Organic compounds can also be synthesized
in the lab.
Why is carbon ideal for making
different compounds?
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Carbon atoms have four valence (outer shell)
electrons, allowing carbon to form covalent bonds
with many elements including hydrogen, oxygen,
phosphorus, sulfur and nitrogen.
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Carbon can also bond to other carbon atoms, which
gives carbon the ability to form chains that are almost
unlimited in length.
These carbon-carbon bonds can be single, double, or
triple.
The chains be straight, branched, or even ring-shaped.
Therefore, carbon is unique in that it can form millions
of different large and complex structures.
What are macromolecules?

They are giant molecules which are made
from many smaller molecules.
How are macromolecules made?
Polymerization is how
macromolecules are
formed!
 This process joins smaller
units (monomers)
together to form larger
compounds (polymers).
(Like placing beads together
to make a necklace.)
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Four Groups of Organic Compounds
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Carbohydrates
Lipids
Nucleic acids
Proteins
….are needed by all living things.
Carbohydrates
(sugars)
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main source of energy for organisms
can also be used for structural purposes
made of C, H, and O; usually in a 1:2:1 ratio
The monomers of carbohydrates are called
monosaccharides: glucose, fructose (in fruits)
and galactose (in milk).
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The breakdown of monosaccharides supplies
immediate energy through cellular respiration.
usually end in –ose.
Carbohydrates cont’d
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Extra sugar is
stored as
macromolecules
called
polysaccharides.
Polysaccharides are
made from
monosaccharides.
Carbohydrate
video
Uses of Polysaccharides

Animals store extra sugar as glycogen.
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Glycogen stored in your muscle supplies energy
for contractions.
Glycogen stored in your liver is released when
glucose in your blood runs low.
Plants store excess sugar as starch.
–
Can also make cellulose, a strong, rigid fiber
used for support in cell walls.
Lipids
(fats, oils, and waxes)
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uses:
–
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long-term energy storage,
insulation,
waterproof covering,
part of cell membranes,
chemical messengers (steroids)
contain mostly C, H & O
generally not soluble in water
Lipids
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Many lipids are formed when a glycerol molecule combines
with fatty acids.
If all carbon atoms have only single bonds, the lipid is
saturated. It holds as many hydrogen atoms as possible.
Lipids

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If there is at least one
double bond between
carbon atoms, the lipid
is unsaturated.
Unsaturated lipids like
cooking oils tend to be
liquid at room
temperature.
Nucleic Acids
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store and transmit genetic
information
contain H, C, N, O, and
phosphorus (P)
The monomers of nucleic
acids are nucleotides
which contain three parts:
–
–
–
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a 5-carbon sugar
a phosphate group,
a nitrogen base.
examples: DNA and RNA
Proteins are macromolecules.
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contain C, H, O, N, & most also have sulfur
(S)
The monomers of proteins are amino acids
which contain:
–
an amino group, a carboxyl group, and a variable
R-group.
Proteins have many functions
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Provide structural support in
bones and muscles,
Form parts of cell
membranes,
Function as hormones to
regulate the body,
Form antibodies to protect
against infection,
Increase the rate of
chemical reactions to name
a few.
• When the amino acids join, they form a polymer
called a polypeptide. The monomers are held
together by peptide bonds.
• More than 20 different amino acids are found in
nature.
• Since the R-group varies, it allows for much
variety. That is why proteins have so many
functions.
Proteins have
four levels of
organization.
• This allows for the
unique shape of
proteins.
• Shape is very
important; if a protein
is not the right shape,
it will not work.
Enzymes – a special type of protein
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A type of protein, which speeds up a
chemical reaction.
Without enzymes, several reactions in cells
would never happen.
Proteins