Warm-Up (Ch. 3 Review) Which of the following is a hydrophobic material: paper, table salt, wax, sugar, or pasta? What kind of bonds are broken when water vaporizes? If the pH of a lake is 4.0, what is the hydrogen ion [H+] concentration of the lake? What is the hydroxide [OH-] concentration?

Chapter 4 Warm-Up Work with the person next to you and sort the organic compounds into categories. How many categories did you create? Why? What are they?

What do you remember about organic molecules? Complete the chart (on the back of Ch. 2 notes) with everything you can remember about each of the 4 organic compounds. NO TALKING. Now, compare your chart with someone else's and add to yours. What are you still missing?

Carbon and the Molecular Diversity of Life Chapter 4 Carbon and the Molecular Diversity of Life

You Must Know The properties of carbon that make it so important.

Why study Carbon? All of life is built on carbon Cells ~72% H2O ~25% carbon compounds carbohydrates lipids proteins nucleic acids ~3% salts Na, Cl, K… Why do we study carbon -- is it the most abundant element in living organisms? H & O most abundant C is the next most abundant

I. Importance of Carbon Organic chemistry: branch of chemistry that specializes in study of carbon compounds Organic compounds: contain Carbon (& H) Major elements of life: CHNOPS Carbon can form large, complex, and diverse molecules

I. Importance of Carbon Organic chemistry is the study of carbon compounds C atoms are versatile building blocks bonding properties 4 stable covalent bonds Carbon chemistry = organic chemistry Why is it a foundational atom? What makes it so important? Can’t be a good building block if you only form 1 or 2 bonds. H C H H H

II. Diversity of Carbon It has 4 valence electrons (tetravalence) It can form up to 4 covalent bonds Most frequent bonding partners: H, O, N

II. Diversity of Carbon Bonds can be single, double, or triple covalent bonds.

II. Diversity of Carbon Hydrocarbons Combinations of C & H non-polar not soluble in H2O hydrophobic stable very little attraction between molecules a gas at room temperature methane (simplest HC)

II. Diversity of Carbon Carbon can form large molecules 4 classes of macromolecules: carbohydrates, proteins, lipids, nucleic acids

II. Diversity of Carbon Molecules can be chains, ring-shaped, or branched

II. Diversity of Carbon Forms isomers Molecules have same molecular formula, but differ in atom arrangement different structures  different properties/functions Structural Isomer Cis-Trans Isomer Sterioisomers Varies in covalent arrangement Differ in spatial arrangement Mirror images of molecules

Isomers Molecules with same molecular formula but different structures (shapes) different chemical properties different biological functions Same formula but different structurally & therefore different functionally. Molecular shape determines biological properties. Ex. Isomers may be ineffective as medicines 6 carbons 6 carbons 6 carbons

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

Drug manufacturing: Thalidomide = “good” sterioisomer  reduce morning sickness “bad” sterioisomer  cause birth defects “good” converts to “bad” in patient’s body Now used to treat cancers, leprosy, HIV

Fig. 4.8 The pharmacological importance of enantiomers

III. Functional Groups Parts of organic molecules that are involved in chemical reactions Affect reactivity makes hydrocarbons hydrophilic increase solubility in water

Viva la difference! Basic structure of male & female hormones is identical identical carbon skeleton attachment of different functional groups interact with different targets in the body different effects For example the male and female hormones, testosterone and estradiol, differ from each other only by the attachment of different functional groups to an identical carbon skeleton.

III. Functional Groups Behavior of organic molecules depends on functional groups Most common functional groups: Hydroxyl Carbonyl Carboxyl Amino Sulfhydryl Phosphate Methyl

Hydroxyl –OH organic compounds with OH = alcohols names typically end in -ol ethanol

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

Carboxyl –COOH C double bonded to O & single bonded to OH group compounds with COOH = acids fatty acids amino acids

Amino -NH2 N attached to 2 H compounds with NH2 = amines amino acids NH2 acts as base ammonia picks up H+ from solution

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

Phosphate –PO4 P bound to 4 O connects to C through an O lots of O = lots of negative charge highly reactive transfers energy between organic molecules ATP, GTP, etc.

Building Blocks of Life Macromolecules Building Blocks of Life 2007-2008

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

Polymers Long molecules built by linking repeating building blocks in a chain monomers building blocks repeated small units covalent bonds H2O HO H • great variety of polymers can be built from a small set of monomers • monomers can be connected in many combinations like the 26 letters in the alphabet can be used to create a great diversity of words • each cell has millions of different macromolecules Dehydration synthesis

How to build a polymer Synthesis joins monomers by “taking” H2O out You gotta be open to “bonding! Synthesis joins monomers by “taking” H2O out one monomer donates OH– other monomer donates H+ together these form H2O requires energy & enzymes enzyme H2O HO H Dehydration synthesis Condensation reaction

How to break down a polymer Breaking up is hard to do! Digestion add H2O to breakdown polymers reverse of dehydration synthesis cleave off one monomer at a time H2O is split into H+ and OH– H+ & OH– attach to ends requires enzymes releases energy H2O HO H enzyme Most macromolecules are polymers • build: condensation (dehydration) reaction • breakdown: hydrolysis An immense variety of polymers can be built from a small set of monomers Hydrolysis Digestion

Biochemistry Basics

THINK, PAIR, SHARE Consider the POLAR molecules in Model 2. In general, the presence of what element(s) make a molecule polar? What property do atoms of these elements have that help make the molecules they are in polar? Can non-polar molecules also have these elements? If yes, what distinguishes a non-polar molecule from a polar molecule? O, N a difference in the electronegativity of carbon and the other element. (dipole) Yes; non-polar molecules have a symmetrical arrangement, no dipole, no charges at their end (balanced)

THINK, PAIR, SHARE In chemistry there is a saying “like dissolves like,” which means things will mix with or dissolve into each other best when their polarities are similar. Is water polar or nonpolar? Is oil polar or nonpolar? Which of the substances in Model 2 would dissolve well in water? Explain. Which of the substances in Model 2 would dissolve well in oil? Explain. Would you expect to find more polar or more nonpolar molecules in a vertebrate bloodstream? Polar molecules: lactic acid, valine, glucose, lactose, adrenaline, dopamine, adenine Nonpolar molecules: fatty acid, cholesterol, vit. A, testosterone Polar – blood is mostly water/polar

THINK, PAIR, SHARE Refer to Model 2. What is another term for a polar molecule? What is another term for a nonpolar molecule? hydrophilic hydrophobic

Work in Small Groups Use your table of functional groups to answer questions 13-17. Be ready to explain your answers to the class.

-COOH When lactic acid dissolves in water it loses (gives up) a proton/H+ ion. This creates >H+ in the water, which lowers the pH of the solution.

-NH2 When adrenaline dissolves in water it gains (takes up) a proton/H+ ion. This creates <H+ in the water (or more –OH-) , which raises the pH of the solution.

<7 >7 >7 =7