The Chemistry Of Organic Molecules

Evolution

The diversity of biological life is the result of changes in DNA sequences, one of the many organic molecules found in cells.

Nature Of Science

An understanding of a molecule's structure provides insight into its function.

Biological Systems

Organic molecules form the functional basis for all cellular systems.

Organic Chemistry

The chemistry of living organisms.

Inorganic Chemistry

The chemistry of nonliving matter.

Biomolecules

Carbohydrates, lipids, proteins, and nucleic acids.

Functional Group

A specific combination of bonded atoms that always reacts in the same way.

Functional Groups Table

Isomers

Organic molecules that have identical molecular formulas but different arrangements of atoms.

Polymers

Constructed by linking together a large number of the same type of subunit, called a monomer.

Dehydration Reaction

The equivalent of a water molecule (that is, an -OH - hydroxyl group - and an -H - hydrogen atom -) is removed as subunits are joined.

Hydrolysis Reaction

An -OH group from water attaches to one subunit, and an -H from water attaches to the other subunit.

Carbohydrates

Almost universally used as an immediate energy source in living organisms, but in some organisms they also have a structural function.

Monosaccharides

Consists of only a single sugar molecule and are commonly called simple sugars.

Pentoses

Monosaccharides with 5 Carbon.

Hexoses

Monosaccharides with 6 Carbon.

Ribose/Deoxyribose

Pentose sugars that are significant because they make up the structural backbone, respectively, in the nucleic acids RNA and DNA.

Disaccharide

Contains two monosaccharides that have joined during a dehydration reaction.

Polysaccharides

Long polymers of monosaccharides; due to their length, they are sometimes referred to as complex carbohydrates; some types function as short-term energy storage molecules.

Lipids

Class of organic compounds that tend to be soluble in nonpolar solvents; includes fats and oils.

Fats

(Triglycerides) the primary lipid used by animals for both insulation and long-term energy storage.

Oils

Triglycerides in plants.

Triglycerides

Composed of fatty acids and glycerol subunits.

Fatty Acid

Molecule that contains a hydrocarbon chain and ends with an acid group.

Saturated Fatty Acid

Lacks double bonds between the carbon atoms and contain as many hydrogens as they can hold.

Unsaturated Fatty Acid

Have double bonds in the carbon chain, which reduces the number of bonded hydrogen atoms.

Glycerol

A 3-carbon compound with three -OH groups.

Phospholipids

Basically triglycerides, except that in place of the third fatty acid attached to glycerol, there is a polar phosphate group.

Steroids

Lipids with structures that are entirely different from those of triglycerides and phospholipids; contains a complex of 4 carbon rings (cholesterol, estrogen, progesterone, testosterone).

Waxes

Long-chain fatty acids are connected to carbon chains containing alcohol functional groups.

Proteins

Polymer of amino acids; often consisting of one or more polypeptides and having a complex three-dimensional shape.

Amino Acid

Organic molecule composed of an amino group and an acid group; covalently bonds to produce peptide molecules.

Peptide Bond

Type of covalent bond that joins two amino acids.

Peptide

Two or more amino acids bonded together.

Polypeptide

A chain of many amino acids joined by peptide bonds.

(Shape of Proteins) Primary Structure

This level of structure is determined by the linear sequence of amino acids, coded for in the genes of the DNA.

(Shape of Proteins) Secondary Structure

Hydrogen bonding between amino acids causes the polypeptide to form an alpha helix or a pleated sheet.

(Shape of Proteins) Tertiary Structure

Interactions of amino acid side chains with water, covalent bonding between R groups, and other chemical interactions determine the folded three-dimensional shape of a protein.

(Shape of Proteins) Quaternary Structure

This level of structure occurs when two or more folded polypeptides interact to perform a biological function.

Nucleic Acids

Composed of nucleotides and have the ability to store information, including the instructions for life, and conduct chemical reactions.

RNA (Ribonucleic Acid)

Another diverse type of nucleic acid that has multiple uses; a temporary copy of a gene in the DNA that specifies what the amino acid sequence will be during the process of protein synthesis.

Coenzymes

Non-protein organic molecule that aids the action of the enzyme to which it is loosely bound.

ATP (Adenosine Triphosphate)

A nucleotide that stores large amounts of energy needed for cellular reactions and for various other energy-requiring processes in the cell.