Carbon based Life&

The Structure and Function of

Macromolecules

Chapter 4-5

Macromolecules Chapter 4-5 2

Outline

Organic vs Inorganic

Functional Groups and Isomers

Macromolecules – 4 major classes: CarbohydratesLipidsProteinsNucleic Acids

-recall: small vs lrg, ionic vs covalent

Ex: amino, carboxyl:

- Think, “starchy foods and sugars”

- Think, “fatty foods and oils”

- Think, “meat and beans (legumes)”

- Think, “genes, herdity, nucleus, cell regulation”

Macromolecules Chapter 4-5 3

Organic MoleculesInorganic – Chemistry of elements other than carbonOrganic – Carbon-based chemistry

Usually associatedliving systems

Often associated with nonliving matter

Often quite large, withmany atoms

Always withfew atoms

Alwayscovalent bonding

Usuallyionic bonding

Always containcarbon and hydrogen

Usually with+ & - ions

OrganicInorganicExamples:

NaCl – sodium chlorideSiO2 –

silicondioxide NaHCO3 –sodium

bicarbonate

Examples:C6H12O6 – glucose

C8H18 - octane

Macromolecules Chapter 4-5 4

Carbon Atom

Carbon atoms:Contain a total of 6 electronsOnly four electrons in the outer shellVery diverse as one atom can bond with up to four other atoms

Often bonds with other carbon atoms to make hydrocarbonsCan produce carbon chains like propane, butane, octane – may be linear or branched

Can produce ring forms like cyclohexane

- The core of “carbon based life forms”

Macromolecules Chapter 4-5 5

Fig. 4.5 p61

Macromolecules Chapter 4-5 6IsomersA. Structural Isomers

Isomers - organic molecules that have: Identical molecular formulas, butDiffering internal arrangement of atoms

C5H12 C5H12

Macromolecules Chapter 4-5 7IsomersB. Geometrical Isomers = Enantiomer

Macromolecules Chapter 4-5 8

Functional Groups and Isomers

Functional groups:Specific combinations of bonded atomsAttached as a group to other molecules­Always react in the same manner, regardless of where attached­Determine activity and polarity of large organic molecules

Many functional groups, but only a few are of major biological importance

Macromolecules Chapter 4-5 9

Fig. 4.9 p65

Macromolecules Chapter 4-5 10

Macromolecules Chapter 4-5 11

Macromolecules Chapter 4-5 12

Polar; some sugarsExample: Acetone

Polar, forms H-bonds; some sugarsand amino acids Example: EthanolR OH

R HC O

R RCO

R OHC O

R HN H

R SH

Biologically ImportantFunctional Groups (Text. P. 63)

Thiols

Phosphate

AminesAmino

CarboxylicAcidsCarboxyl

Ketones

AldehydesCarbonyl

AlcoholsHydroxylCompoundStructureGroup

Sulfhydryl

R RPO

OHOrganic

Phosphates

Significance

Polar; some sugarsExample: Formaldehyde

Polar, acidic; fats and amino acidsExample: Acetic acid

Polar, basic; amino acidsExample: Tryptophan

Disulfide Bonds; some amino acidsExample: Ethanethiol

Polar, acidic; some amino acids,Nucleic AcidsExample: Adenosine triphosphate