2 Questions. 2 minutes.

1. Which of these covalent bonds is/are polar?a) O—Hb) C—Hc) C—C

2. Identify a chemical group with a polar covalent bond and one that has a nonpolar covalent bond. For the polar group, indicate which atom is electronegative.

Chapter 5

Structure & Function of Macromolecules

Polymers and their Monomers!

• These are polymers…• What monomer

components are they made of?– Carbohydrates– Proteins– Nucleic acids

• These are monomers…• Can you match them to

the correct polymer?

– Amino acids– Nucleotides– Monosaccharides

How do we put the monomers together to form a polymer?

05_02Polymers_A.swf

05_05Disaccharides_A.swf

05_21aPrimaryStructure_A.swf

What about lipids?

05_11Fats_A.swf

Why is this molecule a “lipid”?

What kind of chemical bond links monomers together?

• Monosaccharides• Amino acids• Lipid components• Nucleotides

• Glycosidic bond• Peptide bond• Ester bond• Phosphodiester bond

Theme: Structure & Function• A macromolecule’s function(s) is/are determined by

its structure!

• Some examples……

Proteins are another compelling example of structure-function relationships

• 4 levels of structure in proteins:– Primary– Secondary– Tertiary– Quaternary

Primary Protein Structure

• How many molecules of water are required to completely hydrolyze a polypeptide consisting of 11 amino acids?

• What makes each of the 20 different amino acids unique?

• What determines primary protein structure?

• Why is primary structure so important in proteins?

• How many different polypeptides are possible in a chain consisting of 12 amino acids?

Secondary Protein Structure05_21bSecondaryStructure_A.swf

• What determines secondary structure?

• What is the relationship between primary and secondary structure?

Tertiary Protein Structure

05_21cTertiaryStructure_A.swf

• What causes tertiary structure?

• How is tertiary structure related to primary and to secondary structure?

Quaternary protein structure05_21dQuaternaryStructure_A.swf

• What causes quaternary structure?

• How might a change in amino acid sequence affect quaternary structure?

What is denaturation?

What causes denaturation? WHY?

Summary…

Structural variation = Functional Variation

05T_01GeneRegulatoryProt_A.swf05T_01ContractileProtein_A.swf

05T_01DefensiveProteins_A.swf

05T_01TransportProteins_A.swf 05T_01Enzymes_A.swf

Nucleic Acids!

• DNA – genetic material• RNA – ribosomal, transfer, or messenger RNA• Nucleotides – cAMP, ATP (functional n.t.’s)

• What is the relationship between DNA and protein structure?

Review…

• How do nucleotide bases pair up with one another?

• WHY??

Structure-Function (again??!!)

• The structure of DNA inspired Watson and Crick to state that they saw “inherent in its structure a mechanism for its own replication”– An important feature, given its function !