2 Introduction: All compounds can be classified in 2 broad categories: Organic compounds- Contain carbon and hydrogen atomsInorganic compounds- Can have one or the other, but do not contain both carbon and hydrogen atoms
3 A. Most of your body’s molecules are organic compounds. Macromolecules are built from small organic compounds the same way a railroad train is built, by linking a lot of smaller units together into long chains.Large carbon compounds are built up from smaller simpler molecules called monomers (mono = one )Monomers can bind to one another to form complex molecules known as polymers (poly = many)A polymer consists of repeated, linked units, which can also bind forming large polymers called Macromolecules. (macro = large)
4 Monomers link to form polymers through a chemical reaction called condensation reaction or dehydration synthesis. During the formation of polymers, Water (H2O), is released or is the by-product of the reaction.The breakdown of some complex molecules, such as polymers, occurs through a process known as hydrolysis.Hydrolysis is the reverse of a condensation reaction. The addition of water, to some polymers can break the bonds that hold them together.
5 There are four main types of macromolecules found in living organisms: CarbohydratesLipidsProteinsNucleic Acids
6 I. CarbohydratesComposed of carbon, hydrogen, and oxygen atoms in the proportion of 1 : 2 : 1General formula: (CH2O)n where n is the number of carbon atoms.Example: The sugar glucose is a small carbohydrate; its n equals 6. Therefore its chemical formula is C6H12O6.The building blocks (or monomers) of carbohydrates are monosaccharides.
7 Monosaccharides are simple sugars (saccharide = sugar). Examples: Glucose: commonly found in blood of animalsGalactose: a simple sugar found in milkFructose: commonly found in fruitGlucose and Fructose both have the formula C6H12O6, Sometimes compounds may have the same formula, however they have different structures/ arrangements. In such cases, those compounds are called isomers.Disaccharides contain 2 monosaccharides joined by dehydration synthesis. Examples:Lactose: commonly found in milk, made up of Galactose + GlucoseSucrose: “table sugar”, transported in plants, made up of Fructose + Glucose
8 Polysaccharides are carbohydrates formed from linking individual sugars into long chains. Examples: Starch: a common storage form of glucose in plants (breads, pasta, potatoes)Cellulose: a polysaccharide contained in the cell walls of plants; gives strength and rigidity to plant cells.Glycogen: a common storage form of glucose in animals (stored in the muscles and liver to be used as quick energy)
9 II. Lipids (include fats, oils, waxes, etc.) Class of macromolecules that do not dissolve in waterLipids usually serve one of three functions:Energy storagestructural support in cell membranes (phospholipids)serve as reactants (starting materials) for metabolic reactionsFatty acids are the building blocks (or monomers) that make up most lipids.A common lipid that contains fatty acids is a triglyceride. Triglycerides (referred to as neutral fats) are glycerol linked to three fatty acids (in the shape of an “E”) by condensation reaction.
10 III. ProteinsProteins are organic compounds composed mainly of carbon, hydrogen, and nitrogen atoms.Proteins are the construction materials for body parts such as hair, skin, nails, and blood.Amino acids are the building blocks (or monomers) that make up most proteinsThere are 20 different kinds of amino acids that humans use.One important group of proteins - enzymes - help control chemical reactions by acting as catalysts. Catalysts speed up reactions by lowering activation energy.
11 IV. Nucleic AcidsNucleic Acids are complex organic molecules that store genetic information in the cell.Nucleotides are the building blocks (or monomers) that make up most nucleic acids.Nucleotides consist of a sugar (pentose) + base (nitrogenous) + phosphate.Example- DNA nucleotide:Main types of nucleic acidsDNA = Deoxyribonucleic acidIs the genetic information inside the nucleus of cellsRNA = Ribonucleic acidInstructions which code for protein synthesis
13 DescriptionLipidsNucleic AcidsProteinsCarbsCommonly called fats and oilsContain carbon, hydrogen, and nitrogenContain peptide bondsDNA and RNA are examplesFollow the general formula (CH2O)nForm skin, blood, hair, musclesLactose and cellulose are examplesMade up of amino acidsMade up of nucleotidesMost consist of 3 fatty acids bonded to a glycerolUsed for long-term energy storageXXXXXXXXXXX