CHAPTER 3
BIOCHEMISTRY
CARBON COMPOUNDS
• Although water is the primary medium
for life on earth, most of the molecules from
which living organisms are made are based
on the element _________.
• All compounds can be classified in two broad
categories: ______ compounds and _________
compounds
• Organic compounds are made primarily of carbon
atoms.
• Inorganic compounds do not contains carbon atoms.
CARBON BONDING
• A carbon atom has 4 electrons in its
outermost energy level, therefore readily
forms four ______ bonds with the atoms of
other elements.
• Unlike other elements, however, carbon also
bonds with other carbon atoms forming
straight chains, branched chains, or rings.
http://www.youtube.com/
watch?v=QnQe0xW_JY4&lis
t=SP3EED4C1D684D3ADF
FUNCTIONAL GROUPS
• In most organic compounds, clusters of atoms,
called _______groups, influence the
characteristics of the molecules they compose
and the chemical reactions the molecules
undergo.
• The common functional groups:
- Hydroxyl
- Carboxyl
http://www.youtube.com
/watch?v=dV_mufczkAw
- Amino
- phosphate
LARGE CARBON MOLECULES
• Many carbon compounds are built up from
smaller, simpler molecules called ________.
• A polymer is a molecule that consists of
repeated, linked monomers.
• Large polymers are called ______________.
Dehydration synthesis
• Monomers link to form polymers through a chemical
reaction called a __________ reaction.
• Each time a monomer is added to a polymer, a water
molecule is released.
hydrolysis
• In addition to building polymers through
condensation reactions, living organisms also have to
break down polymers.
• The breakdown of polymers occurs through a
process called __________.
MOLECULES OF LIFE
• _______ main classes of organic compounds
are essential to the life processes of all living
things: (macromolecules)
1.
2.
3.
4.
Carbohydrates
Proteins
lipids
Nucleic acids
CARBOHYDRATES
http://www.youtube.com/watch?v=M6ZLDJluj6I
• Carbohydrate is a fancy way of saying “______.“
• What's It Used For?
A carbohydrate is called an organic compound, because it is made up of a
long chain of carbon atoms. Sugars provide living things with ______ and act
as substances used for structure.
• Saccharides
Scientists also use the word ___________ to describe sugars. If there is only
one sugar molecule, it is called a monosaccharide. If there are two, it is a
disaccharide. If there are three, it is a trisaccharide. You get the idea.
• Carbohydrates can exist as:
1. Monosaccharides – a monomer of a carbohydrate
(simple sugar)
- formula: (CH2O)n n= any whole number from 3 to 8.
* The most common monosaccharide are glucose
,fructose and _______
2. Disaccharide – two monosaccharides can
combine in a condensation reaction to form a
_______sugar.
Ex: the monosaccharides fructose and glucose can
combine to form the dissaccharide sucrose.
3. Polysaccharide – a __________molecule
composed of three or more monosaccharides.
Ex: the polysaccharide glycogen, consists of
hundreds of glucose molecules.
http://www.youtube.com/watch?v=_z
m_DyD6FJ0
PROTEINS
Proteins are made of ________. Even though a
protein can be very complex, it is basically a long
chain of amino acid subunits all twisted around like
a knot.
• Amino Acids – There are_____ different amino
acids. Amino acids are used in every cell of your
body and are used to build the proteins you need
to survive.
• The ______ groups (R-group) are what make each
amino acid different from the others.
Amino acid structure
• All amino acids share a basic structure. Each amino
acid contains a central ______ atom, covalently
bonded to 4 other atoms or functional groups. A
hydrogen atom (H), an amine group (NH2 ), a carboxyl
group (COOH) and a side chain/R –group.
Dipeptides & Polypeptides
• Dipeptide – In a condensation reaction, two
amino acids bond to form a dipeptide. The
two amino acids form a covalent bond called a
peptide bond.
• Polypeptide- very long chains of several
amino acids.
• Proteins are composed of one or more
polypeptides.
http://www.youtube.com/watch?v=2Jgb_
DpaQhM
Enzymes
• Enzyme-RNA or ______ molecules that act as
biological ___________. (catalyst- reduce the
amount of activation energy that is needed for
a reaction to take place.)
• Enzyme reactions depend on the fit between
the __________ and the enzyme. The folds on
the enzymes are the active site where the
substrate binds.
Enzyme structure
http://www.youtube.com/watch?v=XTUm-75PL4
LIPIDS
• When you think of ______, you should know that they are
lipids. Lipids are also used to make steroids and waxes. So, if
you pick out some earwax and smell it, that's a lipid, too!
• Lipids include: triglycerides, phospholipids, steroids and
waxes.
• Fatty acids
long carbon ________ that make up most lipids.
The two ends of the fatty acid molecule have
different properties. The carboxyl end is
hydrophilic (attracted to water molecules).
The Carbon end is hydrophobic (water
fearing).
• Triglycerides- composed of ______ molecules of
fatty acid joined to one molecule of the alcohol
glycerol.
• Ex: butter,
Fats in red
meat
• Phospholipids – composed
of ______ fatty acids attached
to a molecule of glycerol.
Ex: cell membrane
• Waxes- type of structural lipid consisting of a
long fatty-acid chain joined to a long _________
chain. Waxes are used to coat and protect things
in nature.
• Steroids- molecules composed of four fused
carbon rings with various functional groups
attached to them.
http://www.youtube.com/watch?v=VGHD9e3y
RIU
NUCLEIC ACIDS
• Nucleic acids are very large complex organic
molecules that store and _______ important
information in the cell.
• Two major types: -Deoxyribonucleic acid (DNA)
- Ribonucleic acid (RNA)
DNA- contains information that determines the
characteristics of an organism and ________ cell
activity.
RNA – stores and transfers information from DNA
that is essential for the _____________ of
proteins.
• Both DNA and RNA are composed of thousands
of linked monomers called ________. Each
nucleotide is made of a phosphate group, a five
carbon sugar, and a ring-shaped nitrogenous
base.
http://www.yo
utube.com/wat
ch?v=NNASRkI
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LETS REVIEW
• http://www.youtube.com/watch?v=H8WJ2KE
NlK0