ORGANIC COMPOUNDS


Carbon forms the backbone of organic compounds by forming carbon chains.
Most organic molecules consist of basic units that are repeated over and over.
These basic units are called monomers. The long chains of monomers form larger molecules called polymers. These monomers are joined together by condensation reactions.

Condensation reaction: a reaction that joins two monomers and releases a molecule of water. (also called dehydration synthesis)

Hydrolysis reactions = break down polymers into monomers
Water molecules combine with parts of the monomers.

There are 4 major groups of organic compounds:
1. Carbohydrates
2. Lipids
3. Proteins
4. Nucleic acids


CARBOHYDRATES: Cn(H2O)n

Monosaccharides = single sugars = C6H12O6
These three monosaccharides are isomers (have the same formula but different chemical structures):
Glucose (also called dextrose or blood sugar)
Fructose
Galactose

Disaccharides = double sugars = C12H22O11
Sucrose is made by combining glucose + fructose
Maltose is made by combining glucose + glucose
Lactose is made by combining glucose + galactose

Polysaccharides = many sugars
Commonly called starches:
Glycogen = animal starch
Cellulose = a plant starch found in cell walls


LIPIDS: Fats, oils, waxes, sterols

Fats are made of Glycerol + fatty acids
Fatty acids consist of chains of 14 - 22 carbons, plus oxygens, and hydrogens.
Glycerol is a 3-carbon chain similar to the alcohol propanol.

Triglycerides are fats made by combining 1 glycerol + 3 fatty acids.

Cholesterol is a sterol or steroid. It is used by the body to make the hormones testosterone, estrogen, and progesterone.

Saturated fats hold all the hydrogen atoms they can hold. They contain no double-bonded cardons. Unsaturated fats contain double-bonded carbons and therefore contain less hydrogen atoms. Saturated fats tend to be solid at room temperature, are more common in animal products, and are linked to higher levels of cholesterol and heart disease. Unsaturated fats tend to be liquid at room temperature, are more common in plant products, and are generally accepted to be healthier. Real butter would contain saturated fats. Margarine contains mostly unsaturated fats.

PROTEINS: are the basic building blocks of living things, and are made of chains of amino acids (20 diff. kinds).

Each amino acid consists of a(n):
Amino group - NH2
Acid group - COOH
Hydrogen group - H
R - group - different for each of the 20 kinds.

Peptide bonds - connect the amino group of one amino acid to the acid group of another amino acid.

Dipeptide - two amino acids joined together

Polypeptide - 3 or more amino acids joined together

Fibrous proteins: proteins that are either coiled or pleated in shape.
Alpha structure - coiled
Beta structure - pleated
Ex: muscle, spider webs, wool, horns

Globular proteins are fibrous chains that are twisted and coiled into globs.
Ex: Hemoglobin


ENZYMES: Enzymes are proteins that are chemical catalysts in the body.
Catalyst = control the rate of a reaction without being affected by the reaction.
Enzymes regulate the chemical reactions that occur in the body by forming chemical bonds between the enzyme and its substrate. These bonds unlock some of the bonds in the substrate, providing the activation energy to get reactions going.

Enzymes only fit specific molecules and reactions.
Substrate = the molecule that an enzyme fits