Organice Compounds - molecules of life, consist of one or more elements covalently bonded to carbon atoms

Hydrocarbons - have only hydrogen atoms attached to a carbon backbone

Functional groups - single atoms or clusters of atoms covalently bonded to the carbon backbone

Enzymes - a class of proteins which makes specific metabolic reactions proceed faster than they would on their own

5 classes of reactions:

	Functional-group transfer - one molecule gives up a functional group, which 	another molecule accepts

	Electron transfer - one or more electrons stripped from one molecule are donated 	to another molecule

	Rearrangement - a juggling of internal bonds converts one type of organic 	compound into another

	Condensation - through covalent bonding, two molecules combine to form a 	larger molecule

	Cleavage - A molecule splits into two smaller ones

Polymer - large molecule with three to millions of subunits, which may or may not be identical

Monomers - the subunits of polymers

hydrolysis - a cleavage reaction

Only living cells synthesize carbohydrates, lipids, proteins, and nucleic acides

Carbohydrates consist of carbon, hydrogen, and oxygen in a 1:2:1 ratio (however, there are exceptions)

monosaccaride - simplest carbohydrate, one monomer of sugar

oligosaccharide - a short chain of two or more sugar monomers that are bonded covalently

polysaccharides - straight or branched chains of many sugar monomers, often hundred or thousands of the same or different kinds
Lipids 
	mainly hydrocarbons that show very little tendency to dissolve in water, although 	they readily dissolve in nonpolar substances. 
	
	certain lipids are the main reservoirs of stored energy, others are structural 	materials in cells

fatty acids - lipids; can be unsaturated (1+ double bonds in their backbone), or saturated (single bonds only in backbone)

Triglycerides (neutral fats) - body’s most abundant lipids and richest energy source

Phospholipids - main materials of cell membranes, which have two layers of lipids

Sterols - have no fatty acid tails; cholesterol is the main type in animal tissues

Waxes - lipids that repel water, wax secretions help keep feathers dry

proteins - most diverse biological molecules; 

amino acid - small organic compound that consists of an amino group, a carboxyl (acid) group, a hydrogen atom, and one or more atoms known as its R group

There are twenty kinds of amino acids available

dipeptide - forms when two amino acids bond together in a peptide bond
polypeptide chain - forms when three or more amino acids bond together in peptide bond

fibrous proteins - polypeptide chains organized as strands or sheets
globular proteins - polypeptide chains folded in compact, rather rounded shapes. most enzymes are globular.

primary structure of protein - sequence of amino acids in a polypeptide chain; unique for each type of protein

Secondary structure of protein - hydrogen bonds form at regular, short intervals along polypeptide chain, give rise to a coiled or extended pattern

Tertiary structure of protein - a polypeptide chain that is folded as a result of its bend-producing amino acids and R-group interactions 

hemoglobin - oxygen-transporting protein 

Quaternary structure - two or more polypeptide chains have become joined together by numerous weak interactions (such as hydrogren bonds) and sometimes by covalent bonds between sulfur and atoms of R groups

lipoproteins - form when certain proteins circulating in blood combine with cholesterol, triglycerides, and phospolipids 

glycoproteins - have linear or branched oligosaccharides covalently bonded to them

denaturation - the breaking of weak bonds of a protein or any large molecule that disrupts its three-dimensional shape

nucleotides - small organic compounds with a sugar, at least on phosphate group, and a base

ATP - a nucleotide that has a string of three phosphate groups attached to its sugar component

coenzymes - enzyme helpers that accept hydrogen atoms and electrons stripped from molecules at a reaction site and transfer them elsewhere

nucleic acids - large, single or double stranded molecules

DNA - deoxyribonucleic acid; a long, double strand of nucleotides twisted helically

RNA - ribonucleic acid - single nucleotide strands