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BiomoleculesBiomolecules

Lab #3Lab #3

Today Today

Quiz #2 – 15 minutesQuiz #2 – 15 minutes

Objectives and Introduction to Biomolecules – Objectives and Introduction to Biomolecules – 20 minutes20 minutes

SafetySafety

Today’s Lab Instructions – 10 minsToday’s Lab Instructions – 10 mins

Experiments - ~ 70 Experiments - ~ 70 minutesminutes

Clean Up Clean Up

SummarySummary

ObjectivesObjectivesDescribe the distinct features of three of four classes of Describe the distinct features of three of four classes of organic moleculesorganic moleculesDifferentiate between monomers and polymersDifferentiate between monomers and polymersIdentify reducing sugars, polysaccharides, lipids, amino Identify reducing sugars, polysaccharides, lipids, amino acids and proteins using diagnostic reagentsacids and proteins using diagnostic reagentsConduct nutritional assessments from case studiesConduct nutritional assessments from case studies

OBJECTIVESOBJECTIVESDescribe the functions of the major classes of biomoleculesDescribe the functions of the major classes of biomoleculesExplain how dehydration synthesis causes molecular bondsExplain how dehydration synthesis causes molecular bondsCompare the different bonds that help define the major Compare the different bonds that help define the major classes of biomoleculesclasses of biomoleculesDescribe the reactive groups of the major biomolecules & Describe the reactive groups of the major biomolecules & explain how they relate to the basic chemical structure of explain how they relate to the basic chemical structure of each class of biomoleculeseach class of biomoleculesUse diagnostic reagents to identify biomolecules & explain Use diagnostic reagents to identify biomolecules & explain the chemical basis for the teststhe chemical basis for the testsDesign & present an experiment to test for the presence of Design & present an experiment to test for the presence of biomolecules in food materialsbiomolecules in food materialsExplain how the chemistry of biomolecules relates to FDA Explain how the chemistry of biomolecules relates to FDA food labels, & how you can use this knowledge to make wise food labels, & how you can use this knowledge to make wise food choicesfood choices

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Biomolecules: The BasicsBiomolecules: The BasicsOrganic molecules are necessary for biological Organic molecules are necessary for biological processes.processes.

Organic molecules contain Organic molecules contain carboncarbon..

4 major types of organic molecules:4 major types of organic molecules:– CarbohydratesCarbohydrates– LipidsLipids– ProteinsProteins– Nucleic Acids (We’ll look at these in a future lab.)Nucleic Acids (We’ll look at these in a future lab.)

Similarities Between Biomolecules:Similarities Between Biomolecules:– All Contain CarbonAll Contain Carbon– Most Contain H, O, N, S and/or PMost Contain H, O, N, S and/or P– ALL Life on Earth is made up of CarbonALL Life on Earth is made up of Carbon

Building Blocks of LifeBuilding Blocks of LifeEach Each Macromolecule Macromolecule is comprised of building block is comprised of building block molecules calledmolecules called monomers monomers::– Monosaccharides Monosaccharides carbohydrates carbohydrates– Fatty Acids and Glycerol Fatty Acids and Glycerol Lipids Lipids– Amino Acids Amino Acids Protein Protein

Macromolecule:Macromolecule: A giant molecule formed by the joining of A giant molecule formed by the joining of smaller molecules, usually by a condensation reaction. smaller molecules, usually by a condensation reaction.

MonomerMonomer- - The subunit that serves as the building block of a The subunit that serves as the building block of a polymer.polymer.

PolymerPolymer-- A long molecule consisting of many similar or identical A long molecule consisting of many similar or identical monomers linked together.monomers linked together.

Functional groups Functional groups The components of organic The components of organic molecules that are most molecules that are most commonly involved in commonly involved in chemical reactions are known chemical reactions are known as as functional groupsfunctional groups

Each functional group behaves Each functional group behaves consistently from one organic consistently from one organic molecule to anothermolecule to another

Provide a way to differentiate Provide a way to differentiate between different between different biomoleculesbiomolecules

http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/G/Groups_5.gif

Hydroxyl GroupHydroxyl Group– Found in alcohols (ex. ethanol) and sugars Found in alcohols (ex. ethanol) and sugars – Polar - increases the solubility of moleculesPolar - increases the solubility of molecules

– OH (not OHOH (not OH-- hydroxide ion) hydroxide ion)

Where are the Hydroxyl groups in the glucose Where are the Hydroxyl groups in the glucose and in the ethanol?and in the ethanol?

ethanol

Carbonyl Group Carbonyl Group

Found in Found in Carbohydrates:Carbohydrates:

Two typesTwo types– AldehydeAldehyde

terminal terminal

– KetoneKetoneinternalinternal

– One or the other on One or the other on every monosaccharideevery monosaccharide

In fatty acids AND amino In fatty acids AND amino acidsacids

Acidic propertiesAcidic properties

Double Bond between Double Bond between Carbon and OxygenCarbon and Oxygen

Single Bonds: Carbon to Single Bonds: Carbon to Hydroxyl Hydroxyl

Written as COOH or Written as COOH or C02HC02H

Carboxyl GroupCarboxyl GroupCarboxyl GroupCarboxyl Group

Amino Group Amino Group

– In every amino acidIn every amino acid– Nitrogen atom attached to two hydrogen atoms Nitrogen atom attached to two hydrogen atoms

Amino Group

Monomer – a single molecule that can Monomer – a single molecule that can combine to form polymerscombine to form polymers

Polymer – long chains of monomersPolymer – long chains of monomers

Dehydration Synthesis and HydrolysisDehydration Synthesis and Hydrolysis

Dehydration SynthesisDehydration Synthesis– Monomers are connected by an enzymatic removal of waterMonomers are connected by an enzymatic removal of water– One monomer provides a hydroxyl group and the other provides One monomer provides a hydroxyl group and the other provides

a hydrogena hydrogenResult is the release of a water moleculeResult is the release of a water molecule

HydrolysisHydrolysis– Covalent Bonds connecting monomers into polymersCovalent Bonds connecting monomers into polymers– A Hydrogen atom and hydroxyl group from a split water A Hydrogen atom and hydroxyl group from a split water

molecule attaches where the bond used to bemolecule attaches where the bond used to be1 H(+) Atom1 H(+) Atom

1 Hydroxyl Group (split from a water molecule)1 Hydroxyl Group (split from a water molecule)

Attach where the bond used to beAttach where the bond used to be

Examples of Examples of Dehydration and Dehydration and HydrolysisHydrolysis

Which one of these is Which one of these is also called a also called a condensation condensation reaction?reaction?

Examples of Examples of Dehydration and Dehydration and HydrolysisHydrolysis

Which one of these is Which one of these is also called a also called a condensation condensation reaction?reaction?

Carbohydrates (Saccharides)Carbohydrates (Saccharides)

Four major functions:Four major functions: – Supply carbon for synthesis of other biomoleculesSupply carbon for synthesis of other biomolecules– Structural components in cells and tissuesStructural components in cells and tissues– Fuel (glucose)Fuel (glucose)– Store glucose (polysaccharides)Store glucose (polysaccharides)

Three types:Three types:– MonosaccharidesMonosaccharides– DisaccharidesDisaccharides– PolysaccharidesPolysaccharides

Defined by carbonyl group Defined by carbonyl group – AldehydeAldehyde– KetoneKetone

Monosaccharides (Basic Unit of Carbohydrates)Monosaccharides (Basic Unit of Carbohydrates)

Simple sugars Classified by the number of carbons they contain

Trioses Pentoses Hexoses

May Exist as Rings (Stable) or Linearly (Unstable)

glucose

DisaccharidesDisaccharides Consist of 2

monosaccharides

Linked via a condensation reaction (Dehydration Synthesis)

Linked by a Glycosidic Bond

PolysaccharidesPolysaccharidesChains of linked Chains of linked monomersmonomers

AmyloseAmylose– Linear chain of Linear chain of

several hundred several hundred glucose moleculesglucose molecules

AmylopectinAmylopectin– Branched chains of Branched chains of

several thousand several thousand glucose moleculesglucose molecules

Starch in plantsStarch in plants

Glycogen in animalsGlycogen in animals

AmylopectinAmylopectin– Branched chains of Branched chains of

several thousand several thousand glucose moleculesglucose molecules

Starch in plantsStarch in plants

Glycogen in animalsGlycogen in animals

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Reducing Sugars:Reducing Sugars:

Contain a free aldehyde or ketone Contain a free aldehyde or ketone group (carbonyl)group (carbonyl)

Reducing sugars reduce something Reducing sugars reduce something elseelse– Includes:Includes:

All monosaccharidesAll monosaccharides

Disaccharides where one aldehyde or Disaccharides where one aldehyde or ketone group is freeketone group is free

Testing for SaccharidesTesting for Saccharides– Benedicts TestBenedicts Test

Tests for the presence or absence Tests for the presence or absence of reducing sugarof reducing sugar– A reducing sugar is a sugar with A reducing sugar is a sugar with

free aldehyde or ketone groupfree aldehyde or ketone groupFree- not used in the bond Free- not used in the bond between monosaccharides. All between monosaccharides. All monosaccharides are reducing monosaccharides are reducing sugars.sugars.

Positive test results red-orange-Positive test results red-orange-yellow coloryellow color

Testing for SaccharidesTesting for Saccharides

Lugol’s TestLugol’s Test– Indicates the presence Indicates the presence

or absence of starchor absence of starch– Positive test results Positive test results

black/purple colorblack/purple color

All our tests today will be All our tests today will be qualitative not qualitative not quantitative (specific quantitative (specific numerical measurement)numerical measurement)

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LipidsLipidsNonpolarNonpolar molecules molecules– Composed of long chains of carbon and Composed of long chains of carbon and

hydrogenhydrogen

Lipid molecules includeLipid molecules include::– Fats, Oils, Steroids, PhospholipidsFats, Oils, Steroids, Phospholipids

Monomers (for triglycerides)Monomers (for triglycerides)– glycerol and fatty acidsglycerol and fatty acids

Major functions includeMajor functions include::– Energy storageEnergy storage– Material for membranesMaterial for membranes

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LipidsLipidsSaturated vs. UnsaturatedSaturated vs. Unsaturated– Saturated lipidsSaturated lipids--

All bonds between carbon & hydrogen are All bonds between carbon & hydrogen are singlesingle bonds bondsNo carbon-carbon double bondsNo carbon-carbon double bondsStraight ChainsStraight ChainsSolid at Room temperatureSolid at Room temperature

– Unsaturated lipidsUnsaturated lipids--Some carbon-carbon bonds are Some carbon-carbon bonds are doubledouble bonds bonds

– Kinked Chains where double bonds are presentKinked Chains where double bonds are presentKinks prevent molecules from packing tightly togetherKinks prevent molecules from packing tightly together

Plants and Fish Fats (oils) are liquid at room temperaturePlants and Fish Fats (oils) are liquid at room temperature

Saturated FatsSaturated Fats Unsaturated FatsUnsaturated Fatshave fatty acids with no carbon-have fatty acids with no carbon-carbon double bondscarbon double bonds

There is a hydrogen at every There is a hydrogen at every possible locationpossible location

The molecule has straight chainsThe molecule has straight chains

Saturated fats are solid at room Saturated fats are solid at room temperaturetemperature

Most animal fats are saturatedMost animal fats are saturated

Contributes to cardiovascular Contributes to cardiovascular diseasedisease

have fatty acids with one or more have fatty acids with one or more carbon-carbon double bondscarbon-carbon double bondsThe molecule has kinked chains The molecule has kinked chains where there is a carbon-carbon where there is a carbon-carbon double bondsdouble bondsPlants and fish fats, known as oils, Plants and fish fats, known as oils, are liquid at room temperatureare liquid at room temperatureThe kinks provided by the double The kinks provided by the double bonds prevent the molecules from bonds prevent the molecules from packing tightly togetherpacking tightly together

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LipidsLipidsTriglyceridesTriglycerides are solid lipids (fats) that are stored in human tissue OR are solid lipids (fats) that are stored in human tissue OR liquid lipids (oils) that are stored in plant tissue. liquid lipids (oils) that are stored in plant tissue. – Store more energy than any other moleculeStore more energy than any other molecule

Triglycerides are formed by attaching 3 fatty acid molecules to a Triglycerides are formed by attaching 3 fatty acid molecules to a glycerol molecule through a glycerol molecule through a condensationcondensation reactionreaction..– Functional group for glycerol (an alcohol) = Functional group for glycerol (an alcohol) = hydroxylhydroxyl group (OH) group (OH)

– Functional group for fatty acid (a carboxylic acid) = Functional group for fatty acid (a carboxylic acid) = carboxylcarboxyl group group (COOH)(COOH)

PhospholipidsPhospholipidsMake up the cell membraneMake up the cell membraneConsist of: Consist of: – a polar head (hydrophilic) a polar head (hydrophilic) – a nonpolar tail (hydrophobic)a nonpolar tail (hydrophobic)

Testing for LipidsTesting for LipidsSudan IVSudan IV– A nonpolar dyeA nonpolar dye– Bonds to other nonpolar moleculesBonds to other nonpolar molecules– Positive test results Positive test results

Cloudy emulsion of dispersed lipid droplets Cloudy emulsion of dispersed lipid droplets which are red color due to the Sudan IVwhich are red color due to the Sudan IV

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ProteinsProteinsStructural support, storage, transport of other substances, and intercellular Structural support, storage, transport of other substances, and intercellular signalingsignaling– ALL Enzymes are ProteinsALL Enzymes are Proteins

All Proteins have a complex 3D ShapeAll Proteins have a complex 3D Shape

Monomers = Monomers = amino acidsamino acids (there are 20 amino acids used by biological organisms)(there are 20 amino acids used by biological organisms)

Amino acids contain:Amino acids contain:– An An aminoamino (NH (NH3 3 ) group) group– A A carboxylcarboxyl (COOH) group. (COOH) group.

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Proteins and Amino AcidsProteins and Amino AcidsWhen amino acids are linked together via a When amino acids are linked together via a condensationcondensation reactionreaction, they , they form a form a proteinprotein..

The chemical bond between each pair of amino acids is called a The chemical bond between each pair of amino acids is called a peptide peptide bondbond..– Carboxyl Group of one Amino Acid joins the amino group of another amino Carboxyl Group of one Amino Acid joins the amino group of another amino

acidacid

Polypeptides: polymers of proteinsPolypeptides: polymers of proteins– Proteins consist of one or moreProteins consist of one or morePolypeptides folded and coiledPolypeptides folded and coiledinto a specific formationinto a specific formation

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Proteins and Amino AcidsProteins and Amino Acids

When long chains of amino acids form When long chains of amino acids form proteins, the chemical properties of the proteins, the chemical properties of the amino acids cause the protein to take amino acids cause the protein to take on more complex shapes:on more complex shapes:

Proteins are used for:Proteins are used for:– Structural supportStructural support– Transport of substancesTransport of substances– Cell signalingCell signaling– EnzymesEnzymes

All enzymes are made of protein. All enzymes are made of protein. Enzymes regulare metabolism by Enzymes regulare metabolism by selectively accelerating chemical reactionsselectively accelerating chemical reactions

Testing for ProteinsTesting for Proteins

Biuret TestBiuret Test– React with peptide bondsReact with peptide bonds– Positive test results purplePositive test results purple

NinhydrinNinhydrin– Tests for single amino acidsTests for single amino acids– Reacts with free amino Reacts with free amino

groupsgroups– Positive test resultsPositive test results

Purple- straight chain Purple- straight chain amino acidamino acid

Yellow- ring chain amino Yellow- ring chain amino acid (proline)acid (proline)

Lab Safety – Biology 111 Lab 3 - Lab Safety – Biology 111 Lab 3 - BiomoleculesBiomolecules

Goggles and closed-toed shoes are required!Goggles and closed-toed shoes are required!

Gloves need to be worn when handling all reagents. Refer to the lab manual for Gloves need to be worn when handling all reagents. Refer to the lab manual for safety notices. Some materials such as Ninydrin and Ninhydrin-collidine are safety notices. Some materials such as Ninydrin and Ninhydrin-collidine are corrosive corrosive andand toxic. toxic. Other chemicals are Other chemicals are flammableflammable..

Closely monitor all hot plates. Immediately turn off when not in use and use hand Closely monitor all hot plates. Immediately turn off when not in use and use hand protectors when handling any beakers placed on hot plates. Keep all solvents away protectors when handling any beakers placed on hot plates. Keep all solvents away from heat sources. from heat sources.

Chromatography solvent is highly flammable with Chromatography solvent is highly flammable with toxic, volatile fumes. toxic, volatile fumes. Keep tightly Keep tightly closed when not in use and keep away from all heat sources. closed when not in use and keep away from all heat sources.

Dispose of any solutions containing the following reagents in the appropriately Dispose of any solutions containing the following reagents in the appropriately labeled containers on the side counter:labeled containers on the side counter:

– Dispose of chromatography solvent, ethanol, and Sudan IV in the solvent waste Dispose of chromatography solvent, ethanol, and Sudan IV in the solvent waste container.container.

– Dispose of Lugol’s solution, Benedicts reagent, and Biuret’s reagent in the base waste Dispose of Lugol’s solution, Benedicts reagent, and Biuret’s reagent in the base waste container.container.

– Dispose of ninhydrin filter papers in the ninhydrin waste bucket.Dispose of ninhydrin filter papers in the ninhydrin waste bucket.

Keep waste containers closed when not disposing of waste, and do not fill past the Keep waste containers closed when not disposing of waste, and do not fill past the indicated line on waste containers. Inform your TA of any full waste containers.indicated line on waste containers. Inform your TA of any full waste containers.

Do not eat or drink in lab.Do not eat or drink in lab. Ask your TA if there is doubt about any procedure.Ask your TA if there is doubt about any procedure.

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Lab Activity: Testing for the Lab Activity: Testing for the presence of organic moleculespresence of organic molecules

Each Each tabletable will work as a single group. will work as a single group.– Within each group, students will perform different tests.Within each group, students will perform different tests.– When all tests are complete, group members will When all tests are complete, group members will teachteach each each

other how to conduct all of the tests.other how to conduct all of the tests.ProcedureProcedure

How does the test work?How does the test work?

What is a positive / negative result?What is a positive / negative result?

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Lab Activity: Testing for the Lab Activity: Testing for the presence of organic moleculespresence of organic molecules

Organization for each table (8 students):Organization for each table (8 students):– Benedict’s Test for Reducing Sugars- Benedict’s Test for Reducing Sugars- 2 students2 students– Lugol’s Test for Starches- Lugol’s Test for Starches- 2 students2 students– Sudan IV Test for Lipids- Sudan IV Test for Lipids- 1 student1 student– Biuret Test for Proteins- Biuret Test for Proteins- 2 students2 students– Ninhydrin Test for Amino Acids- Ninhydrin Test for Amino Acids- 1 student1 student

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Benedict’s TestBenedict’s Test

Tests for the presence of Tests for the presence of reducing sugarsreducing sugars (reacts with the free aldehyde or (reacts with the free aldehyde or ketone groups)ketone groups)You will fill in the data for Table 3-1.You will fill in the data for Table 3-1.– You will need 8 test tubes to test the 8 solutions in Table 3-1.You will need 8 test tubes to test the 8 solutions in Table 3-1.

Make sure you Make sure you gentlygently shakeshake the solution bottles before you use the solution bottles before you use them.them.10 drops = 1 mL10 drops = 1 mLUse Use parafilmparafilm to mix your solutions with the Benedict’s reagent in the to mix your solutions with the Benedict’s reagent in the test tubes.test tubes.

– WARNING! BENEDICT’S REAGENT IS A WARNING! BENEDICT’S REAGENT IS A CORROSIVECORROSIVE BASEBASE. . DODO NOTNOT COME IN CONTACT WITH THIS CHEMICAL AND COME IN CONTACT WITH THIS CHEMICAL AND DISPOSE IN DISPOSE IN BASEBASE WASTEWASTE CONTAINER. CONTAINER.

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Benedict’s TestBenedict’s Test

A positive test result is A positive test result is anyany color color change.change.

Color changes range from:Color changes range from:– Blue > Green > Yellow > Reddish Blue > Green > Yellow > Reddish

OrangeOrangeOrange and Red indicate the strongest Orange and Red indicate the strongest reducing sugars.reducing sugars.

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Lugol’s TestLugol’s Test

Tests for the presence of Tests for the presence of starchesstarchesYou will fill in the data for table 3-1.You will fill in the data for table 3-1.– Procedure begins on pg. 30Procedure begins on pg. 30– You will need 8 test tubes to test the 8 solutions in Table 3-1 (these are You will need 8 test tubes to test the 8 solutions in Table 3-1 (these are

the same solutions used in the Benedict’s test).the same solutions used in the Benedict’s test).– Make sure you Make sure you gentlygently mixmix the solution bottles before you use them. the solution bottles before you use them.– 10 drops = 1 mL10 drops = 1 mL– Use parafilm to mix your solutions with the Lugol’s reagent.Use parafilm to mix your solutions with the Lugol’s reagent.

– WARNING! LUGOL’S IS A TOXIN (ESPECIALLY WARNING! LUGOL’S IS A TOXIN (ESPECIALLY FOR PEOPLE WITH IODINE ALLERGIES OR FOR PEOPLE WITH IODINE ALLERGIES OR WILSON’S DISEASE). DO NOT COME IN CONTACT WILSON’S DISEASE). DO NOT COME IN CONTACT WITH THIS CHEMICAL AND DISPOSE IN BASE WITH THIS CHEMICAL AND DISPOSE IN BASE WASTE CONTAINER.WASTE CONTAINER.

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Lugol’s TestLugol’s Test

A positive test result is a A positive test result is a blueblue--blackblack color, which indicates color, which indicates the presence of starch.the presence of starch.

Monosaccharides and Disaccharides will test Monosaccharides and Disaccharides will test negativenegative for for Lugol’s.Lugol’s.

Emulsification Test for lipids– Use Ethanol + Sudan IV

• A non-polar dye• Bonds to other non-polar molecules• Positive test results red color

Positive

Negative

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Sudan IV TestSudan IV Test

A positive test is a red A positive test is a red stain left on the filter stain left on the filter paper after rinsing.paper after rinsing.

Thin Layer Chromatography

•Mixed lipids can be separated •Yields a chromatogram•Mixed molecules interact with the solvent (mobile phase) and the silica gel (stationary phase) to separate as solvent moves up •Relationship between distance moved by molecule to distance moved by solvent is specific for the matrix conditions & solvent•Relationship is given by Rf

Origin

Solvent front

Triglyceride

Fatty acidsPhospholipids

s

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Biuret TestBiuret Test

Tests for the presence of Tests for the presence of proteinsproteins by reacting with by reacting with peptidepeptide bondsbonds

You will fill in the data for TableYou will fill in the data for Table– Procedure begins on pg. Procedure begins on pg.

– You will need test tubes to test the solutions You will need test tubes to test the solutions

– Make sure you Make sure you gentlygently mixmix the solution bottles before you use them. the solution bottles before you use them.

– 10 drops = 1 mL10 drops = 1 mL

– Use Use parafilmparafilm to mix your solutions with the Biuret reagent. to mix your solutions with the Biuret reagent.

WARNING! BIURET IS A WARNING! BIURET IS A STRONGSTRONG BASEBASE. AVOID . AVOID CONTACT AND DISPOSE OF IN CONTACT AND DISPOSE OF IN BASE WASTE BASE WASTE CONTAINER.CONTAINER.

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Biuret TestBiuret Test

A positive test is a A positive test is a violetviolet color.color.– Any other color change is a Any other color change is a

negativenegative result. result.

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Ninhydrin TestNinhydrin Test

Tests for the presence of Tests for the presence of freefree amino acids by reacting amino acids by reacting with their with their amino groupsamino groups..You will fill in the data for table.You will fill in the data for table.Make sure you Make sure you gentlygently shakeshake the solution bottles before the solution bottles before you use them.you use them.The test will be done on a piece of filter paper folded The test will be done on a piece of filter paper folded into eights.into eights.– Use Use pencilpencil to label each test area. to label each test area.– Dry each solution on the filter paper before you test it Dry each solution on the filter paper before you test it

with the ninhydrin solution.with the ninhydrin solution.– Dry the filter paper Dry the filter paper againagain after the ninhydrin is added. after the ninhydrin is added.

WARNING! NINHYDRIN IS WARNING! NINHYDRIN IS POISONOUSPOISONOUS. AVOID . AVOID CONTACT AND DO NOT INHALE. CONTACT AND DO NOT INHALE.

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Ninhydrin TestNinhydrin Test

A positive test is either a A positive test is either a purple/violet color OR a yellow purple/violet color OR a yellow color.color.– Yellow indicates the presence of a Yellow indicates the presence of a

specific amino acid, specific amino acid, prolineproline..

– Purple indicates the presence of Purple indicates the presence of any any otherother free amino acid. free amino acid.

Ninhydrin Ninhydrin - Collidine

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Nutrition ActivityNutrition Activity

When the students at your table have shared all of their When the students at your table have shared all of their data and taught each other these different tests:data and taught each other these different tests:

– Read the section on Nutritional AnalysisRead the section on Nutritional Analysis You may do this individually or with others.You may do this individually or with others.

– You need to know:You need to know:How to convert pounds (lbs) to kilograms (kg)How to convert pounds (lbs) to kilograms (kg)

How to How to calculatecalculate BMR (know the equation) BMR (know the equation)

Have a basic understanding of the Have a basic understanding of the Prudent DietPrudent Diet

Clean up Clean up • Dispose of any solutions containing the following reagents in the Dispose of any solutions containing the following reagents in the

appropriately labeled containers on the side counter:appropriately labeled containers on the side counter:– Dispose of chromatography solvent, ethanol, and Sudan IV in the Dispose of chromatography solvent, ethanol, and Sudan IV in the

solvent waste container.solvent waste container.– Dispose of Lugol’s solution, Benedicts reagent, and Biuret’s reagent in Dispose of Lugol’s solution, Benedicts reagent, and Biuret’s reagent in

the base waste container.the base waste container.– Dispose of ninhydrin filter papers in the ninhydrin waste bucket.Dispose of ninhydrin filter papers in the ninhydrin waste bucket.

• Keep waste containers closed when not disposing of waste, and do not fill Keep waste containers closed when not disposing of waste, and do not fill past the indicated line on waste containers. Inform your TA of any full waste past the indicated line on waste containers. Inform your TA of any full waste containers.containers.

• Rinse all used test tubes (after dumping contents in proper waste container) Rinse all used test tubes (after dumping contents in proper waste container) and mortar and pestles and return to the middle of the bench. and mortar and pestles and return to the middle of the bench.

• Replace all bottles and other equipment to the middle of the bench in an Replace all bottles and other equipment to the middle of the bench in an orderly manner.orderly manner.

• Make sure all hot plates are offMake sure all hot plates are off

• Clean all pipettes and return them to the “clean pipette” containerClean all pipettes and return them to the “clean pipette” container

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Learning ObjectivesLearning Objectives

Be able to identify the three classes of organic molecules based on their Be able to identify the three classes of organic molecules based on their functional groups.functional groups.Know the difference between a monomer and a polymer.Know the difference between a monomer and a polymer.– Know the monomers for the organic molecules discussed.Know the monomers for the organic molecules discussed.

Know each of the diagnostic tests performed in classKnow each of the diagnostic tests performed in class– Know the Know the generalgeneral procedure procedure– Know how each test worksKnow how each test works– Know what Know what positivepositive and and negativenegative results look like. results look like.

Nutritional Analysis- You need to know:Nutritional Analysis- You need to know:How to convert pounds (lbs) to kilograms (kg)How to convert pounds (lbs) to kilograms (kg)How to How to calculatecalculate BMR (know the equation) BMR (know the equation)Have a basic understanding of the Have a basic understanding of the Prudent DietPrudent Diet

Chemical Tests:Chemical Tests:TestTest Test forTest for Color Color

beforebeforeColor Color afterafter

DetectsDetects

BenedictsBenedicts

LugolsLugols

Sudan IVSudan IV

BiuretBiuret

NinhydrinNinhydrin

Biomolecules SummaryBiomolecules SummaryBiomoleculeBiomolecule Building Building

BlocksBlocksType of Type of BondBond

Binding Binding MechanismMechanism

ProductsProducts

CarbohydratesCarbohydrates Simple Simple SugarsSugars

GlycosidicGlycosidic DisaccaridesDisaccaridesPolysaccharidesPolysaccharides

LipidsLipids Gylcerol Gylcerol Fatty AcidsFatty Acids

DehydrationDehydration TriglyceridesTriglyceridesPhospholipidsPhospholipidsSteroidsSteroids

ProteinsProteins Amino AcidsAmino Acids PeptidePeptide PolypeptidesPolypeptidesProteinsProteins

Test Test for Color before Color after Positive control, negative control

Benedicts Reducing sugars

Pale blue Pale blue – none, green – low, brown – intermediate, orange red - high

Glucose solution, distilled water

Lugols Starch Yellow Blue - black Potato, distilled water

Sudan IV Lipids Light red Red stained oil droplets

Any oil, distilled water

Biuret Peptide bonds

Very pale blue

Violet Milk, distilled water

Ninhydrin Free amino acids

No Color On drying, may be either purple or yellow

Amino acid methionine, distilled water