Macromolecules  “GIANT MOLECULES”  Made up of thousands of single organic molecules known as monomers.  Formed by a process known as polymerization, in which large molecules are produced by joining small ones together.  The small units (monomers), join together to form large units (polymers)

 Usually consist of many repeating units  Large in size  Some examples: Nucleotide DNA, RNA Nucleic Acids Amino acidPolypeptide Proteins MonosaccharidePolysaccharide Carbohydrates Glycerol & fatty acidsFat (trigylceride) Lipids Subunit(s)ExampleCategory

Carbohydrates, Lipids & Proteins  Simple molecules built by covalent bonding and addition of functional groups.  Biological polymers built of simple molecules  Assembled and disassembled in very similar reactions; condensation and hydrolysis

Carbohydrates  As the name implies, consist of carbon, hydrogen, and oxygen  The basic formula for carbohydrates is CH 2 O, meaning that there is one carbon atom, two hydrogen atoms, and one oxygen atom as the ratio in the structure of carbohydrates  What would be the formula for a carbohydrate that has 3 carbons? C3H6O3C3H6O3

Condensation and Hydrolysis  Condensation - Removal of water molecule  Used to connect monomers together to make polymers  Polymerization of glucose monomers to make starch  Hydrolysis - Addition of water molecule  Used to disassemble polymers into monomer parts  Digestion of starch into glucose monomers  Specific enzymes required for each reaction  Accelerate reaction  Are not used in the reaction (catalysts)  What are the main difference between an inorganic catalyst and biological catalyst? This we will discover!

Synthesis and Degradation of Polymers

Monosaccharides: Single sugar molecules, commonly known as ‘simple sugars’ Appear as white crystals that are soluble and sweet to taste Examples Glucose (blood), Fructose (fruit, honey) & Galactose (does not occur naturally)  Hexoses - Six carbon atoms. Isomers of C 6 H 12 O 6 Ribose and deoxyribose (in nucleotides)  Pentoses – Five carbon atoms. C 5 H 10 O 5 and C 5 H 10 O 4

Disaccharides: Monosaccharide molecules react to form disaccharides – condensation/ dehydration/ elimination reaction (all refer to same reaction type) Also soluble (due to presence of polar OH groups) and sweet to taste Examples: Sucrose Table sugar, maple sugar One glucose and one fructose molecule joined by dehydration Maltose Malt sugar Two glucoses joined by dehydration

Common Monosaccharides, Disaccharides & Polysaccharides

Synthesis = condensation synthesis (can also be called dehydration)  Removal of OH + H forms water, H 2 O  Ether link (or glycosidic link) -O- formed in disaccharide.

11 Glycosidic Linkages in Carbohydrates Water eliminated

Disassembly = hydrolysis Bond between monosaccharide units is broken when reacted with water.  The OH- + H+ ions fill the ether bonding sites.

Polysaccharides  Build up of more than two monosaccharide units by condensation  Again can be disassembled by hydrolysis.

Polysaccharides  Polymers of monosaccharides  Low solubility (non polar); not sweet to taste  Examples: Glycogen  Stored fuel in liver, muscle cells  Polymer of glucose, unbranched  Used for short-term energy storage (digestible by hydrolysis) Starch  Polymer of glucose  Plant equivalent of glycogen  Used for short-term energy storage (digestible by hydrolysis)  Often branched chain  Amylose, corn starch

More polysaccharide examples  Cellulose  Long, coiled polymer of glucose  Very large linear polymer that form bundles  Glucoses connected differently than in starch  Note the different orientations of the –CH 2 OH groups on adjacent glucose monomers above on starch (top) and cellulose (bottom) monomers. Alternating sides in cellulose polymer.  Structural element for plants  Main component of wood and many natural fibers  Indigestible by most animals  Chitin  Polymer of glucose  Each glucose with an amino group  Very resistant to wear and digestion (indigestible)  Arthropod exoskeletons, cell walls of fungi

Starch Structure and Function

Glycogen Structure and Function

Cellulose Structure and Function

Component of plasma membrane Lipids  Insoluble in water  Long chains of repeating CH 2 units  Renders molecule Non Polar  Types of Lipids Medicines Component of plasma membrane; hormones Steroids No-stick pan spray Phospholipids Cooking oils Long-term energy storage in plants and their seeds Oils Butter, lard Long-term energy storage & thermal insulation in animals Fats Human Uses Organism Uses Type

Lipids  Larger group, mainly constructed of C and H, some O  Fats (Triglycerides)  mostly “saturated” fatty acids (single carbon bonds),  unreactive & solid at room temperature  1 glycerol, 3 fatty acids  Oils  “unsaturated” fatty acids,  liquid at room temperature  1 glycerol, 3 fatty acids

Lipids  Phospholipids  1 glycerol molecule + 2 fatty acids (not three like fats & oils) + 1 phosphate-containing acid  Steroids  unlike other lipids, 4-ring structure

 Long-term energy storage  Assembled of glycerol + 3 fatty acids by condensation synthesis.  Backbone of one Glycerol molecule = 3-carbon chain with 3 hydroxyl groups (OH-)  Fatty acid = long carbon backbone with Carboxylic acid at one end  Carboxylic acid connects to –OH on glycerol in condensation reaction  Three fatty acids attached to each glycerol molecule Types of Lipids: Triglycerides (Fats)

Synthesis = condensation  Remove H from glycerol and OH from fatty acids  Creates ester linkage