Macromolecules Macromolecules

Building Complex Building Complex Molecules That Comprise Molecules That Comprise Living ThingsLiving Things

Organic Macromolecules Organic Macromolecules

Contain CarbonContain Carbon

Therefore, each carbon atom can Therefore, each carbon atom can make ____ covalent bonds with make ____ covalent bonds with other types of atoms or additional other types of atoms or additional carbons.carbons.

Question: How many Question: How many electrons does carbon need electrons does carbon need to fill its outer energy level? to fill its outer energy level? Answer: Answer: FourFour

fourfour

In a double bond, carbons share two pairs of electrons

In a triple bond, carbons share three

pairs of electrons

Carbon Atoms Bind to Functional GroupsCarbon Atoms Bind to Functional Groups

Organic Molecules Can Exist as IsomersOrganic Molecules Can Exist as Isomers

Structural Isomers have the same atomsStructural Isomers have the same atomsin different bonding relationshipsin different bonding relationships

Stereoisomers have Stereoisomers have different spatial positioning different spatial positioning

for the same bonding relationshipsfor the same bonding relationships

cis-trans isomers

cis-trans isomers

enantiomers

enantiomers

Macromolecules: Polymers Macromolecules: Polymers Made of Repeating MonomersMade of Repeating Monomers

MacromoleculeMacromolecule Monomer UnitMonomer Unit

CarbohydratesCarbohydrates SugarsSugars

LipidsLipids Fatty acidsFatty acids

ProteinsProteins Amino acidsAmino acids

Nucleic AcidsNucleic Acids NucleotidesNucleotides

Synthesis and Breakdown of Synthesis and Breakdown of Macromolecules Macromolecules

Condensation Condensation or Dehydration or Dehydration SynthesisSynthesis

Removal of water to add Removal of water to add monomer unitsmonomer units

HydrolysisHydrolysis Addition of OH and H Addition of OH and H groups of water to break groups of water to break a bond between a bond between monomersmonomers

Dehydration Synthesis / HydrolysisDehydration Synthesis / Hydrolysis

Dehydration SynthesisDehydration Synthesis

HydrolysisHydrolysis

Nucleic Acid Nucleic Acid Structure and FunctionStructure and Function

DNADNA

RNARNA

ProteinProtein

Information Flow From DNAInformation Flow From DNA

transcriptiontranscription

translationtranslation

replicationreplication(prior to (prior to

cell division)cell division)(ongoing(ongoing cellular cellular metabolism)metabolism)

Gene: sequence of DNA that codes

for a protein

DNA and RNA StructureDNA and RNA Structure

DNADNA

RNARNA

Primary Primary StructureStructure

Chain of Chain of nucleotidesnucleotides

Chain of Chain of nucleotidesnucleotides

Secondary Secondary StructureStructure

Double helixDouble helix Single Single folded chainfolded chain

Three Parts of Nucleotide StructureThree Parts of Nucleotide Structure

NitrogenousNitrogenousBase (1 of 5)Base (1 of 5)

CHCH22CHCH22

HHHH

DeoxyriboseDeoxyriboseoror

RiboseRibose

OOOO

HHHH

OHOHOHOH HHHH

HHHHHHHH

OH

HO P O

O

5-Carbon Sugar5-Carbon Sugar

Phosphate GroupPhosphate Group

NNNNHCHCHCHC

NNNN CCCC

CCCC

CCCC

CHCHCHCH

NNNN

NNNN

NHNH22NHNH22

DNA and RNA StructureDNA and RNA StructureDNADNA RNARNA

PurinePurine bases bases Adenine (A)Adenine (A)

Guanine (G)Guanine (G)

Adenine (A)Adenine (A)

Guanine (G)Guanine (G)

PyrimidinePyrimidine bases bases Cytosine (C)Cytosine (C)

Thymine (T)Thymine (T)

Cytosine (C)Cytosine (C)

Uracil (U)Uracil (U)

5-carbon sugar5-carbon sugar deoxyribosedeoxyribose riboseribose

PhosphatePhosphate POPO44 POPO44

OHOH OHOHOHOH HH

Nucleotide ChainNucleotide Chain

Nucleotides are joined Nucleotides are joined together by dehydration together by dehydration synthesissynthesis

The phosphate of one The phosphate of one nucleotide is joined to nucleotide is joined to sugar of next sugar of next nucleotide, forming a nucleotide, forming a “sugar-phosphate “sugar-phosphate backbone”backbone”

DNA StructureDNA Structure

•Two nucleotide Two nucleotide chains chains•In opposite In opposite orientations orientations•Held together Held together by hydrogen by hydrogen bonds bonds•Twisted into a Twisted into a helix helix

GG

AA

CC

AA

CC

TT

GG

TT

AA

TT

TT

AA

5’ endhas free phosphate

3’ endhas free sugar

3’ end

5’ endA pairs with T

G pairs with C

T A

C G

DNA Secondary StructureDNA Secondary StructureThe Double HelixThe Double Helix

• Two polynucleotide chains are Two polynucleotide chains are wound togetherwound together

• Bases are located inside the helixBases are located inside the helix• Sugar-phosphate groups are on Sugar-phosphate groups are on

the outside as a “backbone”the outside as a “backbone”• Bases are arranged like rungs on Bases are arranged like rungs on

a ladder, perpendicular to the a ladder, perpendicular to the “backbone”“backbone”

• 10 base pairs per turn of the helix10 base pairs per turn of the helix

DNA ReplicationDNA Replication

•DNA chains separateDNA chains separate

•Each chain is used Each chain is used as a pattern to as a pattern to produce a new chain produce a new chain

•Each new DNA helix Each new DNA helix contains one “old” contains one “old” and one “new” chain and one “new” chain

Transcription = Production of RNA UsingTranscription = Production of RNA Using DNA as a Template DNA as a Template

•DNA chains separateDNA chains separate

•ONE DNA chain is used ONE DNA chain is used as a pattern to produce as a pattern to produce an RNA chain an RNA chain

•RNA chain is releasedRNA chain is released and the DNA chains and the DNA chains reform the double-helix reform the double-helix

In DNA In RNA A U T A G C C G

RNA Secondary StructureRNA Secondary StructureSingle, Folded ChainSingle, Folded Chain

• Each RNA has a Each RNA has a unique structure unique structure based on its based on its nucleotide sequencenucleotide sequence

• RNA-RNA Base RNA-RNA Base Pairing RulesPairing Rules– A pairs with UA pairs with U– G pairs with CG pairs with C

• Can linkCan link– bases in proximitybases in proximity– distant base distant base

sequencessequences

Functions of Nucleotides and Nucleic AcidsFunctions of Nucleotides and Nucleic Acids DNADNA Hereditary Material, specifies Hereditary Material, specifies

protein sequencesprotein sequences

RNARNA Intermediate in protein productionIntermediate in protein production

RibozymesRibozymes RNA catalystsRNA catalysts

ATP ATP Energy transferEnergy transfer

GTPGTP Energy transferEnergy transfer

Activator/Inhibitor in Signal Activator/Inhibitor in Signal TransductionTransduction

cAMPcAMP(cyclic AMP)(cyclic AMP)

Secondary messenger in Signal Secondary messenger in Signal TransductionTransduction