Download Building Materials of Life

The Building Materials
of Life
A survey of organic
compounds
Compounds may be organic or inorganic.
Water is the most abundant inorganic
compound in living things.
Carbon dioxide is an inorganic compound
that supplies carbon for living things.
(CO is also inorganic)
Organic compounds contain carbon
(as well as H & O)
• Carbon atoms are special to organic
compounds because they can form
four covalent bonds.
• And they can form chains & ring
structures, as well as single, double or
triple bonds.
Carbon has the ability to form millions of
different, large, complex structures.
Formulas
Organic compounds are often represented
by molecular formulas that tell you the
numbers and kinds of atoms.
Butane
Ethanol
Aspartame
C4H10
C2H5OH
C14H18N2O5
Structural formulas can show you
the arrangement of the atoms in the
molecule.
Molecules composed of many molecular units
or “building blocks” are called polymers.
Polymers often refer to molecules of many
smaller molecules. These smaller building
blocks called monomers.
• Very Large complex polymers are
macromolecules.
 Polymers are produced by condensation
reactions in which water molecules are
removed between monomers.
(Dehydration synthesis)
 They are broken down into simpler
molecules by hydrolysis in which water is
added between monomers.
Organic Compounds are
hydrocarbons…
If they consist of only carbon and
hydrogen such as methane, propane
etc.
Gasoline contains hydrocarbons.
Carbohydrates
Carbohydrates include sugars, starches
and cellulose. They are the primary source
of energy for living things.
• Plants store sugar in starch molecules,
while animals can store sugar as
glycogen.
• Plant cell walls are made of cellulose.
Carbohydrates have a ratio of
H : O that is 2:1
Example: Sucrose = C12H22O11
I - SUGARS
The breakdown of sugars,
such as glucose, provides
immediate energy to cells.
Carbohydrates exist as:
• monosaccharides – single sugar
• disaccharides – double sugar
• polysaccharides - many sugars
The building blocks of
carbohydrates are simple sugars
called monosaccharides.
Isomers
Notice that the monosaccharides below all
have the same chemical formula.
Compounds that have the same
chemical formula, but different
chemical structures are called Isomers.
-OSE
Notice that all three names have an
ose ending. This always means the
compound is a sugar. (except cellulose)
Bonding Monosaccharides
Monosaccharides are the monomers that
are chemically bonded to make more
complex carbohydrates.
Two sugar monomers joined together
chemically produce dissacharides
II – STARCHES
Starches are the storage form of
sugars in plants. Plants store
carbohydrate products as complex
carbohydrates called starch.
There may be 500 to 1000 glucose
monomers in one starch molecule. There
may be attached branching chains of
monomers.
• Starch is the principle carbohydrate
found in plant seeds and tubers;
important sources of starch include
corn, potato and rice.
• Starch exists in the form of granules, each
of which consist of several million
amylopectin molecules together with an
even larger number of amylose molecules.
(Since amylopectin is a much larger molecule
than amylose, the mass of amylopectin is
typically 4 to 5 times that of amylose in starch.)
Chitin
Chitin is a polysaccharide found in arthropod
exoskeletons (crustaceans, arachnids and
insects) It is Earth’s second most abundant
polysaccharide.
It is also found in fungal cell walls.
Proteins
Proteins are organic
compounds made up of mostly
carbon, hydrogen, oxygen &
nitrogen.
Proteins make up many structures,
such as cell organelles, muscles,
hair and fingernails.
Some proteins are called
enzymes which help
chemical reactions to take
place (they’re called
catalysts).
AMINO ACIDS
• Building blocks of proteins are amino
acids. (they are the monomers)
• Proteins vary by the kinds, amount and
arrangement of the amino acids. (There
are 20 different types)
BASIC AMINO ACID STRUCTURE:
• Amino acids can be taken in as food, or
formed within living cells.
• Amino acids that cannot be produced
by the body are called “essential”
amino acids and must be provided by
diet.
Examples of Amino Acids:
Formation of Proteins:
Amino acids bond to form proteins through
condensation reactions. (dehydration
synthesis)
Protein = Peptide or
Polypeptide?
Types of Protein
Nutrient/Storage Proteins
• casein (protein in milk)
• albumen (protein in egg whites)
• seed protein
(for the embryonic seed plant)
Structural protein:
• collagen protein,which comes in
sheet,cables or filaments.
(found in body joints,cartilage, tendons, &
skin)
• keratin (fingernails,hair, feathers & horns)
Regulatory protein:
• insulin (regulate glucose levels in blood)
• growth hormone(regulates body growth)
Transport Proteins:
• hemoglobin
(transports O2 & CO2
in the blood)
Protective Proteins:
• antibodies in the immune system
(destroy pathogens, such as viruses and
bacteria cells in the body)
• clotting proteins fibrinogen & thrombin
(help form blood clots when blood
vessels are damaged)
Toxins & Poisons
• snake venom
• bacterial toxins (such as E. coli food
poisoning toxin or C. botulinum
–botulism)
Contractile protein:
• actin & myosin in muscle fibers
(contracts skeletal muscle for
movement)
Motility protein:
• (tubulin protein in microtubles and
cilia & flagella)
Catalysts:
• enzymes speed the rate of chemical
reactions in living organisms. (over 2000
enzymes have been identified)
Lipid Functions
• long term storage of energy
(Fats contain a higher proportion of energy-rich C-H
bonds than carbohydrates and therefore contain more
chemical energy. Lipids store more than twice the energy
per grams as carbohydrates or proteins.)
• long term storage of organic carbon
• forming a major part of all cell
membranes.
• They also cushion organs, water proof
(not water soluble) and insulate
living things.
• Oils and fats are known as triglycerides.
• Three-fatty acid molecules & one glycerol join.
• Three water molecules are formed by a
condensation reaction when making a triglyceride.
Saturated & Unsaturated Fats
• Look at the structural formula of a
triglyceride. If there are any double
bonds in the fatty acid chains of the
triglyceride, it is an unsaturated fat.
(More H can be added to the carbons).
• If there are more than one double
bond in the fatty acids it is
polyunsaturated.
It this triglyceride saturated, unsaturated or
polyunsaturated?
Fats, which tend to be solids at room
temperature, such as animal fats, are
saturated.
(They have only single bonds between
carbon atoms in their fatty acid chain and
have as many H atoms as they can hold.)
If only two fatty acid molecules & a
phosphate group join to a glycerol, a
phospholipid is produced.
hydrophilic – water-loving
hydrophobic – water-fearing
Phospholipids are an important part of
cell membranes. The inability of lipids
to dissolve in water allows the cell
membrane to form a barrier between
the inside and outside of the cell.
Waxes
• A wax consists of a long fatty-acid
chain joined to an alcohol chain.
• They are highly
waterproof, and
in plants form a
protective coating
on outer surfaces.
In animals, protective
layers are also formed
(example: earwax
keeps out microbes)
Steroids
A steroid, unlike most lipids, is
composed of 4 interlocking carbon
rings (not fatty acids) with various
functional groups attached.
(example: testosterone)
Cholesterol
1) It is needed for cell membranes.
2) It is a major component of a nerve cell’s
myelin sheath (outer covering). In a mature
brain, the highest amount of cholesterol is found in the
myelin.
3) Cholesterol may be produced and broken down by the
liver.
4) Too much cholesterol in the blood can form fatty deposits
or blockages in blood vessels which may lead to stroke or
heart disease.
5) Cholesterol exists in two forms:
Low density lipoprotein (LDL) – They tend
to form the deposits in the blood vessels.
(“Bad cholesterol” )
High density lipoprotein (HDL) – They
tend to carry the cholesterol to the liver to
be broken down. “Good cholesterol”
Some plants store food energy
in oils especially in seeds and
fruits.
There is even a special fats produced by
animals for hibernation, dormancy or
periods of migration. (Some hibernating
animals produce a fat called
triacyglycerol).
Hibernating animals collect huge amounts
of body fat, not only for food reserve, but
also as insulation against the cold.
Nucleic Acids
Nucleic acids such as DNA and RNA store
hereditary information for cells. They are
made up of building blocks called
nucleotides.
What is DNA?
• Deoxyribonucleic acid
• DNA is the molecule
of genes.
• It is found in the
chromosomes.
• It holds the
instructions to making
all the proteins in an
organism.
What is DNA’s Structure?
• DNA is a biological polymer made up of
subunits called nucleotides.
• DNA Nucleotides are made up of:
a) 5-carbon deoxyribose
sugar
b) phosphate group
c) nitrogen-containing base
Finally, ATP is the energy
molecule for all cell processes.
It is produced through the
breakdown of glucose during cell
respiration.
ATP
Adenosine triphosphate has a high
energy bond that can release energy
for cell work.