Ch. 5 Warm-Up ActivityCh. 5 Warm-Up Activity

1.1. What are the 4 biologically important What are the 4 biologically important organic compounds, their building blocks organic compounds, their building blocks and an example of each?and an example of each?

2.2. What is the difference between dehydration What is the difference between dehydration synthesis and hydrolysis? When are each synthesis and hydrolysis? When are each used?used?

3.3. What are the 4 structural levels of a protein What are the 4 structural levels of a protein and what bonds are involved in each?and what bonds are involved in each?

4.4. What does it mean when a protein has been What does it mean when a protein has been denatured? What are some possible causes denatured? What are some possible causes for this to happen?for this to happen?

Chapter 5Chapter 5

The Structure and The Structure and Function of Large Function of Large

Biological MoleculesBiological Molecules

You Must KnowYou Must Know• The role of The role of dehydration synthesisdehydration synthesis in the in the

formation of organic compounds and formation of organic compounds and hydrolysishydrolysis in the digestion of organic compounds.in the digestion of organic compounds.

• How to recognize the 4 biologically important How to recognize the 4 biologically important organic compounds (carbs, lipids, proteins, organic compounds (carbs, lipids, proteins, nucleic acids) by their structural formulas.nucleic acids) by their structural formulas.

• The cellular functions of all four organic The cellular functions of all four organic compounds.compounds.

• The 4 structural levels of proteinsThe 4 structural levels of proteins• How proteins reach their final shape How proteins reach their final shape

((conformationconformation) and the ) and the denaturingdenaturing impact impact that heat and pH can have on protein structurethat heat and pH can have on protein structure

Monomers PolymersMacromolec

ules•Small organic •Used for building blocks of polymers•Connects with condensation reaction (dehydration reaction)

•Long molecules of monomers•With many identical or similar blocks linked by covalent bonds

•Giant molecules•2 or more polymers bonded together

ie. amino acid peptide polypeptide protein

smaller larger

Dehydration Reaction(Condensation

Reaction)Hydrolysis

Make polymers Breakdown polymers

Monomers Polymers Polymers Monomers

A + B AB AB A + B

+ H2O

+ + H2O

+

I. CarbohydratesI. Carbohydrates• FuelFuel and and building materialbuilding material• Include simple sugars (fructose) and polymers Include simple sugars (fructose) and polymers

(starch)(starch)

• Ratio of 1 carbon: 2 hydrogen: 1 oxygen or CHRatio of 1 carbon: 2 hydrogen: 1 oxygen or CH22OO

• monosaccharidemonosaccharide disaccharidedisaccharide polysaccharidepolysaccharide• MonosaccharidesMonosaccharides = monomers (ie. glucose, = monomers (ie. glucose,

ribose)ribose)• PolysaccharidesPolysaccharides::

StorageStorage (plants-starch, animals-glycogen) (plants-starch, animals-glycogen) StructureStructure (plant-cellulose, arthropod-chitin (plant-cellulose, arthropod-chitin))

Differ in position & orientation

of glycosidic

linkage

The structure The structure and classification and classification of some of some monosaccharidesmonosaccharides

Linear and ring forms of Linear and ring forms of glucoseglucose

Examples of disaccharide synthesisExamples of disaccharide synthesis

Storage polysaccharides of Storage polysaccharides of plantsplants (starch) and (starch) and animalsanimals (glycogen) (glycogen)

Structural polysaccharides: cellulose & chitin Structural polysaccharides: cellulose & chitin (exoskeleton)(exoskeleton)

II. LipidsII. LipidsA.A. Fats (triglyceride): Fats (triglyceride): store large

amounts of energy (2x carbohydrates), cushions organs and insulates body

Glycerol + 3 Fatty Acids saturated, unsaturated, polyunsaturated

B.B. SteroidsSteroids: cholesterol and hormones

C.C. Phospholipids: Phospholipids: cell membrane hydrophilic head, hydrophobic tails creates bilayer to form cell membrane

Hydrophilic headHydrophobic tail

Ester linkage: between OH

& COOH

Long HC chain: -Polar or non-polar? -Hydrophilic or hydrophobic?

Saturated UnsaturatedPolyunsatura

ted“saturated” with H Have some C=C, result in kinks

In animals In plants

Solid at room temp.

Liquid at room temp.

Eg. butter, lard Eg. corn oil, olive oil

Steroids include cholesterol (shown above) which is the building block for steroid hormones and component of cell membranes

The structure of a phospholipid

Hydrophobic/hydrophilic interactions make a phospholipid bilayer

Overview of protein Overview of protein functionsfunctions

Overview of protein Overview of protein functionsfunctions

Proteins: Proteins: polymers polymers made of made of amino acid amino acid monomersmonomers

III. ProteinsIII. ProteinsFour Levels of Protein Structure:Four Levels of Protein Structure:

1.1. PrimaryPrimary Amino acid (AA) sequenceAmino acid (AA) sequence 20 different AA’s20 different AA’s peptide bonds peptide bonds link AA’slink AA’s

Four Levels of Protein Structure Four Levels of Protein Structure (continued)(continued)2.2. SecondarySecondary

Gains 3-D shape (folds, coils) by H-Gains 3-D shape (folds, coils) by H-bondingbonding

Alpha (α) helix, Beta (Alpha (α) helix, Beta (ββ) pleated ) pleated sheetsheet

Four Levels of Protein Structure Four Levels of Protein Structure (continued)(continued)

3.3. TertiaryTertiary Bonding between Bonding between side chainsside chains (R groups) (R groups) of of

amino acidsamino acids H & ionic bonds, disulfide bridges, van der H & ionic bonds, disulfide bridges, van der

Waals interactionsWaals interactions

Four Levels of Protein Structure Four Levels of Protein Structure (continued)(continued)4.4. QuaternaryQuaternary

2+ polypeptides 2+ polypeptides bond togetherbond together

amino acids amino acids polypeptides polypeptides proteinprotein

Bonding (ionic & H) can create asymmetrical attractions

ChaperoninsChaperonins assist in proper assist in proper folding of proteinsfolding of proteins

• Protein Protein structure and function structure and function are sensitive to chemical and are sensitive to chemical and physical conditionsphysical conditions

• Unfolds or Unfolds or denaturesdenatures if if pHpH and and temperaturetemperature are not optimal are not optimal

change in change in structurestructure = change = change in in functionfunction

IV. Nucleic AcidsIV. Nucleic Acids

Function: carry hereditary infoFunction: carry hereditary info

DNA RNA•Double stranded helix• N-bases: A, G, C, Thymine•Stores hereditary info•Longer/larger•Sugar: deoxyribose

•Single stranded• N-bases: A, G, C, Uracil•Carry info from DNA to ribosomes•tRNA, rRNA, mRNA, RNAi•Sugar: ribose

Nucleotides: monomer of Nucleotides: monomer of DNA/RNADNA/RNA

3 parts: -nitrogen base -pentose sugar -ribose -deoxyribose -P04 group

NucleotideNucleotidephospha

te

5-C sugar

Nitrogenous base

A – TG – C

Purines Pyrimidines

•Adenine•Guanine

•Cytosine•Thymine (DNA)•Uracil (RNA)

•Double ring •Single ring

Building the polymerBuilding the polymer

Nucleic polymerNucleic polymer

• BackboneBackbone• Sugar to POSugar to PO44 bond bond• Phosphodiester bondPhosphodiester bond

• new base added to sugar of previous basenew base added to sugar of previous base• Polymer grow in one directionPolymer grow in one direction

• N bases hang off the sugar-phosphate N bases hang off the sugar-phosphate

backbonebackbone

Pairing of nucleotidesPairing of nucleotides

• Nucleotides bond between DNA Nucleotides bond between DNA strandsstrands

• H bondsH bonds• Purine :: PyrimidinePurine :: Pyrimidine• A :: TA :: T

• 2 H bonds2 H bonds• G :: CG :: C

• 3 H bonds3 H bonds

DNA DNA RNA RNA protein: a protein: a diagrammatic diagrammatic overview of overview of information flow in information flow in a cell.a cell.