Download Sec_2_3 Carbon Compunds

SECTION 2.3
CARBON COMPOUNDS

Organic Chemistry- study of all compounds
that contain bonds between carbon atoms
I. CHEMISTRY OF CARBON
•
Characteristics of Carbon:
1. Carbon atoms have 4 valence electrons
2. Each electron can join with an electron from
another atom to form a strong covalent bond
3. Carbon can bond with many elements such as
•
•
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Hydrogen
Oxygen
Phosphorus
Sulfur
Nitrogen
SPONCH
CHARACTERISTICS OF CARBON
4. Carbon atoms can bond to other carbon atoms
forming chains that are almost unlimited in
length (macromolecules)
Carbon can form single, double or triple bonds.
CHARACTERISTICS OF CARBON
5. Carbon can bond with carbon to form
 Chains
 Branches
 Rings
 No other element has the versatility of carbon!
MACROMOLECULES
Macromolecules- large molecules made from
1000s or 100s of 1000s smaller molecules
 Made by a process of polymerization
 Made of smaller units called monomers
joined together to form polymers (the
monomers can be identical or different!)
ORGANIC COMPOUNDS OR BIOMOLECULES ARE
CLASSIFIED INTO 4 GROUPS:
1.
2.
3.
4.
Carbohydrates
Lipids
Nucleic Acids
Proteins
1. CARBOHYDRATES (C,H,O)
Living things use carbohydrates as their main
source of energy and structural purposes
 The breakdown of sugars, such as glucose
(C6H12O6) supplies immediate energy for all cell
activity

1. CARBOHYDRATES
Extra sugar is stored as complex
carbohydrates known as starches
 Three types of carbohydrates:

a) Monosaccharide- single sugar molecules
•
glucose (blood sugar)
•
galactose (milk)
•
fructose (fruits)
b) Disaccharide- two monosaccharides linked together
 E.g. sucrose (table sugar) = glucose + fructose

lactose (milk sugar) = galactose + glucose
c) Polysaccharide- many monosaccharides joined
together
Ex. Glycogen- animal starch released from your liver
when glucose in blood runs low
Cellulose- plant starch which is tough and flexible.
Major component of wood and paper
Starch - plant starch which is stored in potatoes
and grains
2. LIPIDS (C, H, SOME O)
 The
common categories of lipids are fats,
oils, and waxes
Compounds made mostly from carbon and
hydrogen (very few oxygen atoms)
 NOT soluble in water!
(hydrophobic)
 Used to store energy

2. LIPIDS.
Biological roles:
 energy storage
 insulation: especially prominent
in some mammals and birds
(penguins and seals).

padding (some organs have extra padding of
fat)
2. LIPIDS.
Biological roles:
 components of the
cell membrane (phospholipids
and cholesterol in animals)

Some hormones are steroids (estrogen/
testosterone)
2. LIPIDS

Many lipids are formed when a glycerol
molecule combines with compounds called
fatty acids.
2. LIPIDS



Saturated- carbon atom in a lipids fatty acid chain
is joined to another carbon atom by a single bond
(maximum number of hydrogens!)
Unsaturated- at least one carbon-carbon double
bond in a fatty acid (ex. Olive oil)
Polyunsaturated- fatty acids
contain more than one
double bond (ex. Cooking
oils such as corn, sesame,
canola and peanut oils)
3. NUCLEIC ACIDS (C, H, O, N, P)
Macromolecules that contain hydrogen, oxygen,
nitrogen, carbon and phosphorus
 Nucleotide- individual monomer consisting of
three parts:

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a 5-carbon sugar,
a phosphate group,
a nitrogenous base (A, T, C, or G)
3. NUCLEIC ACIDS
Individual nucleotides can be joined
to form a nucleic acid
 Nucleic acids store and transmit
heredity or genetic information

1.
2.
DNA- deoxyribonucleic acid, double stranded,
(sugar=deoxyribose); stores genetic information
RNA- ribonucleic acid, single stranded,(sugar =
ribose), makes proteins
4. PROTEINS (C, H, O, N)
Macromolecules that contain nitrogen,
carbon, hydrogen, and oxygen
 Monomers are called amino acids


Amino acids are compounds with an amino
group (-NH2) on one end and a carboxyl
group (-COOH) on the other end
4. PROTEINS
 Amino
acids differ from each
other in a side chain called the
R-group, which have a range of
different properties.
 More
than 20 different amino
acids are found in nature.
 This
variety results in proteins
being among the most diverse
macromolecules.
4. PROTEINS
Covalent bonds called peptide
bonds link amino acids together to
form a polypeptide.
 A protein is a functional molecule
built from one or more polypeptides.
4. PROTEINS
Proteins perform many varied functions:
 Control rate of reactions (enzymes)
 Regulate cell processes (hormones)
 Transport substances into or out of cells
 Help fight disease (antibodies)
 Form bones and muscles
4. Proteins: Levels of organization
Proteins have four levels
of structure.
 A protein’s primary
structure is the sequence
of its amino acids.
 Secondary
structure is
the folding or coiling of the
polypeptide chain.
4. PROTEINS: LEVELS OF ORGANIZATION
 Tertiary
structure is the complete,
three-dimensional arrangement of a
polypeptide chain.
 Proteins with more than one chain
have a fourth level of structure
(quaternary), which describes the
way in which the different
polypeptide chains are arranged with
respect to each other. For example,
the protein shown, hemoglobin,
consists of four subunits.