Biological Macromolecules

Carbon 15th most abundant element Can form up to 4 covalent bonds

Carbon Bonding

Functional Groups

Four categories of Biological Macromolecules Carbohydrates Lipids (fats) Proteins Nucleic acids (DNA and RNA)

Introduction Three of the four classes of macromolecules form chainlike molecules called polymers. The repeated units are small molecules called monomers.

Dehydration / Condensation Reaction

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Hydrolysis

carbohydrates

Carbohydrates Energy storage molecule Structural elements in cells and tissues

Monosaccharides Single sugar molecules CH2O Functional groups Hydroxyl Carbonyl Glucose Fructose

Disaccharides Double sugar molecules joined by a glycosidic bond Energy sources and building materials

Isomers

Disaccharides Sucrose Maltose Lactose Cellobiose

Polysaccharides Polymers of monosaccharides Hundreds to thousands of monomers

Cellulose

Starch Starch granules

Glycogen

Chitin

Lipids Contain carbon, hydrogen and oxygen Hydrophobic molecules Soluble in organic solvents – ethanol, ether

Biological Roles Energy Absorbs shock Waterproofing Metabolic water Structural framework Insulation

Fats and oils Fatty acids and glycerol Ester bonds

Saturated fats Fats Maximum hydrogen atoms Solid at room temperature

Palmitic Acid

Unsaturated Fat Oils At least one double bond in the fatty acid Liquid at room temperature

Linolenic Acid

Isomers of Fatty Acids

Hydrogenated Oils

Phospholipids Glycerol molecule 2 fatty acids chains Phosphate group

Steroids 3 – 6 carbon rings 1 – 5 carbon ring

Proteins Polymers of amino acids

Amino acids

Amino Acids

Polypeptides

Proteins Many amino acid chains linked together Enzyme reactions Oxidation / reductions Structure Storage Transport Cell signaling Defense

Protein structure Shape depends on R-groups of amino acids Shape controls function of the protein Primary Secondary Tertiary Quaternary

Primary Structure

Secondary Structure

Tertiary Structure

Disulfide Bridge

Van der waals

Keratin – disulfide bridges

Proteins structure

Denaturing Proteins Loss of 3-dimensional structure Strong acids and alkalis Heavy metals Heat and radiation Detergents and solvents http://www.sumanasinc.com/webcontent/animatio ns/content/proteinstructure.html