Chemistry Joke of the Day a Poem Susan

Chemistry Joke of the Day… a Poem. § Susan was in chemistry. u Susan is no more, § for what she thought was H 2 O u AP Biology was really H 2 SO 4.

Chemistry of Carbon Building Blocks of Life AP Biology 2007 -2008

Why study Carbon? § All of life is built on carbon § Cells ~72% H 2 O u ~25% carbon compounds u § § u AP Biology carbohydrates lipids proteins nucleic acids ~3% salts § Na, Cl, K…

Chemistry of Life § Organic chemistry is the study of § carbon compounds C atoms are versatile building blocks bonding properties u 4 stable covalent bonds u H H C H AP Biology H

Complex molecules assembled like Tinker. Toys AP Biology

Hydrocarbons § Combinations of C & H u non-polar § not soluble in H 2 O § hydrophobic stable u very little attraction between molecules u § a gas at room temperature AP Biology methane (simplest HC)

Hydrocarbons can grow AP Biology

Isomers § Molecules with same molecular formula but different structures (shapes) different chemical properties u different biological functions u 6 carbons AP Biology 6 carbons

Form affects function § Structural differences create important functional significance u amino acid alanine § L-alanine used in proteins § but not D-alanine u medicines § L-version active § but not D-version u AP Biology sometimes with tragic results… stereoisomers

Form affects function § Thalidomide prescribed to pregnant women in 50 s & 60 s u reduced morning sickness, but… u stereoisomer caused severe birth defects u AP Biology

Diversity of molecules § Substitute other atoms or groups around the carbon u ethane vs. ethanol § H replaced by an hydroxyl group (–OH) § nonpolar vs. polar § gas vs. liquid § biological effects! AP Biology ethane (C 2 H 6) ethanol (C 2 H 5 OH)

Functional groups § Parts of organic molecules that are involved in chemical reactions u give organic molecules distinctive properties hydroxyl carbonyl carboxyl amino sulfhydryl phosphate § Affect reactivity makes hydrocarbons hydrophilic u increase solubility in water u AP Biology

Viva la difference! § Basic structure of male & female hormones is identical u u u AP Biology identical carbon skeleton attachment of different functional groups interact with different targets in the body § different effects

Hydroxyl § –OH organic compounds with OH = alcohols u names typically end in -ol u § ethanol AP Biology

Carbonyl § C=O u O double bonded to C § if C=O at end molecule = aldehyde § if C=O in middle of molecule = ketone AP Biology

Carboxyl § –COOH u C double bonded to O & single bonded to OH group § compounds with COOH = acids w fatty acids w amino acids AP Biology

Amino § -NH 2 u N attached to 2 H § compounds with NH 2 = amines w amino acids § NH 2 acts as base w ammonia picks up H+ from solution AP Biology

Sulfhydryl § –SH u S bonded to H § compounds with SH = thiols § SH groups stabilize the structure of proteins AP Biology

Phosphate § –PO 4 u P bound to 4 O § connects to C through an O § lots of O = lots of negative charge w highly reactive § transfers energy between organic molecules w ATP, GTP, etc. AP Biology

Macromolecules Building Blocks of Life AP Biology 2007 -2008

Macromolecules § Smaller organic molecules join together to form larger molecules u macromolecules § 4 major classes of macromolecules: carbohydrates u lipids u proteins u nucleic acids u AP Biology

Polymers § Long molecules built by linking repeating building blocks in a chain u monomers § building blocks § repeated small units u covalent bonds Dehydration Synthesis http: //sciencestage. com/v/621/chemis try-experimentsciencedehydrationsugar. html AP Biology H 2 O HO H H

How to build a polymer § Synthesis u You gotta be open to “bonding! joins monomers by “taking” H 2 O out § one monomer donates OH– § other monomer donates H+ § together these form H 2 O u H 2 O requires energy & enzymes HO H Dehydration synthesis HO H enzyme Condensation reaction AP Biology HO H

How to break down a polymer Breaking up is hard to do! § Digestion u use H 2 O to breakdown polymers § reverse of dehydration synthesis § cleave off one monomer at a time § H 2 O is split into H+ and OH– w H+ & OH– attach to ends requires enzymes HO u releases energy H 2 O u enzyme H Hydrolysis AP Biology Digestion HO H

Any Questions? ? AP Biology 2007 -2008