1. 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?

2. 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?

3. 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?

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

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

6. 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

7. 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

8. 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

9. 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

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

11. 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)

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

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

14. 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

15. 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

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

17. 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

18. Fig. 4.8 The pharmacological importance of enantiomers

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

20. 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.

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

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

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

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

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

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

27. 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.

28. Building Blocks of Life
Macromolecules
Building Blocks of Life

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

30. 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

31. 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

32. 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

35. Biochemistry Basics

36. 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)

37. 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

38. 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

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

40. -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.

41. -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.

42. <7
>7
>7 =7