Macromolecular StructuresMacromolecular Structures

Really Big MoleculesReally Big Molecules

Macromolecular StructuresMacromolecular Structures

Types of Macromolecular StructuresTypes of Macromolecular StructuresCovalent Network SystemsCovalent Network SystemsPolymersPolymers

PlasticsPlasticsBiomoleculesBiomolecules

Covalent NetworkCovalent Network

Covalent Network SolidsCovalent Network SolidsSystems of Interlocking Covalent BondsSystems of Interlocking Covalent BondsNot Individual MoleculesNot Individual MoleculesAll have very high melting pointsAll have very high melting pointsExamplesExamples

CarbonCarbonGraphiteGraphiteDiamondDiamondNanotubesNanotubes

SiliconSiliconSilicon dioxideSilicon dioxide

Silica, Glass, QuartzSilica, Glass, Quartz

GraphiteGraphiteMassive Sets of Fused 6 membered ringsMassive Sets of Fused 6 membered rings

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GraphiteGraphite

PropertiesPropertiesGood lubricantGood lubricantConducts electricityConducts electricityVery high melting pointVery high melting point

DiamondDiamond

Tetrahedral repeating Tetrahedral repeating patternpattern

Very strong network Very strong network of bondsof bonds

Diamond is the Diamond is the hardest substance hardest substance known.known.

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Carbon NanotubesCarbon Nanotubes Similar structure to Similar structure to

graphitegraphite

Sheet of 6 membered Sheet of 6 membered rings rolled into a rings rolled into a tube.tube.

Have high melting Have high melting pointspoints

Very high strengthVery high strength High conductivityHigh conductivity

BuckeyballsBuckeyballs

Not a covalent Not a covalent networknetwork

CC6060 molecule molecule

Many other possible Many other possible spherical spherical arrangementsarrangements FullerenesFullerenes

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SilicaSilica

Has an empirical formula of SiOHas an empirical formula of SiO22

Has a repeating tetrahedral structureHas a repeating tetrahedral structureOxygens are parts of multiple tetrahedra.Oxygens are parts of multiple tetrahedra.

Gives glass and sand their high melting Gives glass and sand their high melting points.points.

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PolymersPolymers

PolymersPolymers

““poly-” = manypoly-” = many ““mer” from mer” from merosmeros = part = part

PolymerPolymer – a chemical compound formed – a chemical compound formed from many smaller molecules.from many smaller molecules.

Requires a little bit of organic chemistry Requires a little bit of organic chemistry shorthand.shorthand.

Organic ShorthandOrganic Shorthand Drawing all those hydrogens gets tediousDrawing all those hydrogens gets tedious

Condense themCondense them

Use a line notationUse a line notation Each red dot represents a carbonEach red dot represents a carbon

It is understood that each carbon has an octet filled It is understood that each carbon has an octet filled out with hydrogen unless otherwise noted.out with hydrogen unless otherwise noted.

PlasticsPlastics

Polymers made from small organic Polymers made from small organic moleculesmoleculesOrganic compounds are made from carbon.Organic compounds are made from carbon.

PolyethylenePolyethylene

Made from Made from ethylene ethylene moleculesmolecules

Used in milk Used in milk cartons (HDPE)cartons (HDPE)

6 pack plastic 6 pack plastic rings (LDPE)rings (LDPE)

C C

H

H H

H

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PolypropylenePolypropylene

Made from propyleneMade from propylene

Used in clothing and Used in clothing and Gladware type Gladware type containers.containers.

C C

CH3

H H

H

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Polyethylene terephthalatePolyethylene terephthalate

Has two monomersHas two monomers EthyleneEthylene Terephthalic acidTerephthalic acid

Used in soda bottles Used in soda bottles (PETE or PET)(PETE or PET)

O

O

O

O

O

O

OH

OH

C C

H

H H

H

TeflonTeflon

PolytetrafluoroethylenePolytetrafluoroethylene

Due to high Due to high electronegativity of electronegativity of fluorine, the structure is fluorine, the structure is not very susceptible to not very susceptible to forming an induced forming an induced dipoledipole Makes a very slippery Makes a very slippery

surfacesurface

C C

F

F F

F

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PolystyrenePolystyrene

Made from styrene Made from styrene monomersmonomers

Can be fluffedCan be fluffed StyrofoamStyrofoam

Can be compactCan be compact Drink lidsDrink lids

CH2

BiopolymersBiopolymers

BiopolymersBiopolymersPolymers made from biomoleculesPolymers made from biomolecules4 Basic Types of Biomolecules4 Basic Types of Biomolecules

Amino AcidsAmino AcidsProteins are amino acid polymersProteins are amino acid polymers

CarbohydratesCarbohydratesStarch and Cellulose are carbohydrate polymersStarch and Cellulose are carbohydrate polymers

LipidsLipidsNucleic AcidsNucleic Acids

DNA and RNA are nucleic acid polymersDNA and RNA are nucleic acid polymers

Amino AcidsAmino Acids

Named for two parts Named for two parts of the structureof the structure

Amine functional Amine functional groupgroup

Carboxylic acid Carboxylic acid functional groupfunctional group

Amino AcidsAmino Acids

The different amino The different amino acids are different in acids are different in one locationone location

R is just a place R is just a place holderholder

The R group in this The R group in this particular case is particular case is called a “side chain”called a “side chain”

Amino AcidsAmino Acids

Amino AcidsAmino Acids

Polymerizing Amino AcidsPolymerizing Amino Acids

Peptide Bond

AspartameAspartame

NutrasweetNutrasweet

Aspartic acidAspartic acid

PhenylalaninePhenylalanine

NH2 CH

CH2

C O

OH

C

O

NH CH

CH2

C

O

OCH3

Protein StructureProtein Structure Proteins fold in on Proteins fold in on

themselves. themselves.

They fold so that They fold so that Nonpolar side chains are Nonpolar side chains are

on the interior of the on the interior of the protein (away from water)protein (away from water)

Polar side chains are on Polar side chains are on the exterior of the protein.the exterior of the protein.

ProteinsProteins

HemoglobinHemoglobin

CollagenCollagen

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CarbohydratesCarbohydrates

Names comes from observation about Names comes from observation about formulasformulasCC66HH1212OO66 – Glucose/Fructose/Galactose – Glucose/Fructose/Galactose

CC1212HH2222OO1111 – Sucrose – Sucrose

CC55HH1010OO55 – Ribose – Ribose

All have a 2:1 ratio of H:OAll have a 2:1 ratio of H:O

Carbohydrate PolymersCarbohydrate Polymers The most important The most important

carbohydrate polymers carbohydrate polymers have glucose monomershave glucose monomers

StarchStarch AmyloseAmylose AmylopectinAmylopectin

CelluloseCellulose

These differ only by how These differ only by how the glucose molecules the glucose molecules connect.connect.

O

OH

HH

H

OH

OH

H OH

H

OH

StarchStarch

Used for glucose Used for glucose storage in plantsstorage in plants

Amylose – linear Amylose – linear structurestructure

Amylopectin – Amylopectin – branched structurebranched structure

CelluloseCellulose

Linear polymerLinear polymer

Forms cell wall of Forms cell wall of plants.plants.

Indigestible by Indigestible by humanshumans

Why are they different?Why are they different?

Why is starch Why is starch digestible and digestible and celluose isn’t?celluose isn’t?

We have the enzyme We have the enzyme necessary to break necessary to break this bond.this bond.

We lack the enzyme We lack the enzyme necessary to break necessary to break down this bond.down this bond.

Nucleic AcidsNucleic Acids

Nucleic acid monomers Nucleic acid monomers are are nucleotidesnucleotides

1.1. Nitrogenous baseNitrogenous base

2.2. Pentose (sugar with Pentose (sugar with 5 carbons)5 carbons)

Ribose = RNARibose = RNA Deoxyribose = DNADeoxyribose = DNA

3.3. PhosphatePhosphate

NO

O

OH

OH

OH

O

P N

NN

NH2

NO

O

OH

OH

OH

O

P N

NN

NH2

OH

Nucleotide PolymerizationNucleotide Polymerization

NO

O

OH

OH

OH

O

P N

NN

NH2

NO

O

OH

OH

OH

O

P

N

NH2

O

+N

OO

OH

O

OH

O

P

N

NH2

O

NO

OOH

OH

O

P N

NN

NH2

OH2

+

Nucleic Acid StructureNucleic Acid Structure

NO

O

OH

O

OH

O

P

N

NH2

O

NO

OOH

OH

O

P N

NN

NH2

DNA Base PairsDNA Base Pairs

DNA DNA Double Double HelixHelix

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RNARNA

RNA can base pair RNA can base pair too.too.

RNA can form helical RNA can form helical structures toostructures too

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RNA and Protein TogetherRNA and Protein Together

RibosomeRibosome