Human Biochemistry B.5-9Human Biochemistry B.5-9

nutrientsnutrients

Food required in the dietFood required in the diet Recommended daily intakeRecommended daily intake Micro less than 0.005% of body mass Micro less than 0.005% of body mass

mg or mg or μμg per dayg per day Vitamins and mineralsVitamins and minerals Needed to produce enzymes or other Needed to produce enzymes or other

substances needed for healthsubstances needed for health

MacronutrientsMacronutrients

For energy and structureFor energy and structure Proteins, carbohydrates, lipidsProteins, carbohydrates, lipids Na,Mg,K,Ca,P,S and ClNa,Mg,K,Ca,P,S and Cl

Dietary mineralsDietary minerals Major minerals–in boneMajor minerals–in bone Calcium,  Calcium,

phosphate, magnesium phosphate, magnesium Major minerals–in electrolytesMajor minerals–in electrolytes Sodium,  Sodium,

potassium, chloride potassium, chloride Minor minerals–in metalloproteinsMinor minerals–in metalloproteins Iron,  Iron,

copper, manganese, iodine, cobalt, copper, manganese, iodine, cobalt, molybdenum, selenium, chromium, fluoride, molybdenum, selenium, chromium, fluoride, zinc zinc

Trace mineralsTrace minerals Nickel, silicon, vanadium, tin  Nickel, silicon, vanadium, tin

Electrolyte resultsElectrolyte results TestTest Patient's ResultsPatient's Results Ref. Ref. RangeRangeUnitsUnits BMPBMP Na Na L124L124 136-145mEq/L 136-145mEq/L K K H5.8H5.8 3.5-5.1mEq/L 3.5-5.1mEq/L CO2 25 23-29mEq/LCO2 25 23-29mEq/L Cl 101 98-107mEq/LCl 101 98-107mEq/L Glucose H107 74-100mg/dLGlucose H107 74-100mg/dL Ca 10.1 8.6-10.2mg/dLCa 10.1 8.6-10.2mg/dL BUN 17 8-23mg/dLBUN 17 8-23mg/dL Creatinine0.9 0.8-1.3mg/dLCreatinine0.9 0.8-1.3mg/dL Key: L=Abnormal Low, H=Abnormal High, Key: L=Abnormal Low, H=Abnormal High,

WNL=Within Normal Limits, *=critical valueWNL=Within Normal Limits, *=critical value

VitaminsVitamins

Needed but not synthesized in the bodyNeeded but not synthesized in the body Water or fat solubleWater or fat soluble Water -filtered out by kidneys and Water -filtered out by kidneys and

excreted excreted Fat -absorbed and stored in fat tissuesFat -absorbed and stored in fat tissues Look at table 21 of the IB data bookletLook at table 21 of the IB data booklet

ADEK fatADEK fat

all others waterall others water

Look at data bookletLook at data booklet Vitamin A (retinol)structureVitamin A (retinol)structure FatFat Important for vision at low light Important for vision at low light

intensityintensity

Look at vitamin C (ascorbic acid)Look at vitamin C (ascorbic acid) WaterWater Cofactor in enzyme reactionsCofactor in enzyme reactions Tissue regeneration after injuryTissue regeneration after injury

D (calciferol)D (calciferol) FatFat Similar in structure to cholesterolSimilar in structure to cholesterol Uptake of CaUptake of Ca+2 +2 by cellsby cells Healthy bones and teethHealthy bones and teeth Get by sunlight or put in milkGet by sunlight or put in milk

Deficiency diseasesDeficiency diseases

Pick one for a report (in pairs)Pick one for a report (in pairs) Vitamin A, Iodine, iron, niacin, Vitamin A, Iodine, iron, niacin,

thiamin, vit. C, D, selenium, proteinthiamin, vit. C, D, selenium, protein Describe disease, pictures?, reasons, Describe disease, pictures?, reasons,

solutionssolutions

General summary of nutrient General summary of nutrient problemsproblems

What is the problem in the USA?What is the problem in the USA? Worldwide causes and solutionsWorldwide causes and solutions do questions 9 and 10do questions 9 and 10

B.6 HormonesB.6 Hormones

Communication systems Communication systems Nervous – electrochemical = quickNervous – electrochemical = quick Endocrine – chemical messengers= Endocrine – chemical messengers=

slowerslower Different types of moleculesDifferent types of molecules Produced in glands (no ducts)Produced in glands (no ducts) Receptors are target cellsReceptors are target cells

HormonesHormones

Another reportAnother report ADH, thyroxine, aldosterone, ADH, thyroxine, aldosterone,

adrenaline, insulin, estrogen, adrenaline, insulin, estrogen, progesterone, testosteroneprogesterone, testosterone

Gland, type of molecule, target cells, Gland, type of molecule, target cells, functionsfunctions

Look at your data booklet on Look at your data booklet on hormoneshormones

Compare cholesterol, Compare cholesterol, estradiol(estrogen), progesterone, estradiol(estrogen), progesterone, testosteronetestosterone

Alike and differencesAlike and differences

Oral contraceptivesOral contraceptives

Prevents ovulationPrevents ovulation Mixture of progesterone and Mixture of progesterone and

estrogenestrogen Prevent release of follicle stimulating Prevent release of follicle stimulating

and luteinizing hormonesand luteinizing hormones No ovulation, simulates pregnancyNo ovulation, simulates pregnancy

Use and abuse of steroidsUse and abuse of steroids

Hormone replacement therapy at Hormone replacement therapy at menopausemenopause

Male steroids (anabolic) androgens Male steroids (anabolic) androgens like testosteronelike testosterone

Enhance male characteristicsEnhance male characteristics Overuse aggressive, liver cancerOveruse aggressive, liver cancer

Do questions 11 and 12Do questions 11 and 12

B.7 EnzymesB.7 Enzymes

Control system of the bodyControl system of the body Biological catalystsBiological catalysts

structurestructure

Globular proteins-several hundred Globular proteins-several hundred amino acidsamino acids

Tertiary and quaternary structures Tertiary and quaternary structures importantimportant

Co-factors binding non-protein Co-factors binding non-protein moleculesmolecules

Organic called coenzymes inorganic Organic called coenzymes inorganic metal ionsmetal ions

Examples vitaminsExamples vitamins

Catalytic actionCatalytic action

Define enzymeDefine enzyme Reactant is a substrateReactant is a substrate Enzyme substrate complexEnzyme substrate complex Active site on the enzyme is a pocket Active site on the enzyme is a pocket

or groove on the surfaceor groove on the surface Enzyme is larger than substrateEnzyme is larger than substrate

http://en.wikipedia.org/wiki/File:Activation_energy.svg

AnimationAnimation Another animationAnother animation

saturationsaturation

3 things this tells us3 things this tells us

Low conc. Rate relates to substateLow conc. Rate relates to substate As conc. Increases enzyme gets tied As conc. Increases enzyme gets tied

upup High conc. Rate constantHigh conc. Rate constant

Michaelis-Menten EquationMichaelis-Menten Equation

VVmaxmax turnover number turnover number # molecules/second# molecules/second

Michaelis constant KMichaelis constant Kmm

½ V½ Vmaxmax

Specific pH and temp.Specific pH and temp. Units of concentrationUnits of concentration Low KLow Kmm quick reaction constant rate quick reaction constant rate

Enzyme activityEnzyme activity

TemperatureTemperature Increase rate as temp goes upIncrease rate as temp goes up At a point the protein denaturesAt a point the protein denatures

Human optimum tends to be 37 Human optimum tends to be 37 ooCC Denaturation usually is irreversibleDenaturation usually is irreversible Lowering temperature only causes Lowering temperature only causes

deactivationdeactivation High fevers can be fatalHigh fevers can be fatal

pHpH

Changes affect the equilibrium Changes affect the equilibrium positionspositions

If it affects the R groups in amino If it affects the R groups in amino acids it will alter the attractive ability acids it will alter the attractive ability thus influences the shapethus influences the shape

Each enzyme has an optimal pHEach enzyme has an optimal pH Extremes cause denaturationExtremes cause denaturation

For humans 7.4For humans 7.4

Heavy metal ionsHeavy metal ions

Lead, copper, mercury and silverLead, copper, mercury and silver PoisonousPoisonous React with SH groups on cysteine to React with SH groups on cysteine to

make S-metalmake S-metal Changes shapeChanges shape

Chemical inhibitorsChemical inhibitors

Competitively at the active siteCompetitively at the active site Non-competitively at another areaNon-competitively at another area

Competitive inhibitorsCompetitive inhibitors

Takes a higher substrate Takes a higher substrate concentration to reach Vconcentration to reach Vmaxmax

Chymotrpsin is an enzyme which hydrolyzes peptides at the Chymotrpsin is an enzyme which hydrolyzes peptides at the carbonyl side of tyr or phe or trp (i.e. those that have an aromatic carbonyl side of tyr or phe or trp (i.e. those that have an aromatic side chain. In the graphic on the left, the substrate and the side chain. In the graphic on the left, the substrate and the irreversible inhibitor are shown in the active site pocket. In the irreversible inhibitor are shown in the active site pocket. In the case of the inhibitor the reaction starts in the same way as with case of the inhibitor the reaction starts in the same way as with the substrate, but the end result is that the inhibitor is covalently the substrate, but the end result is that the inhibitor is covalently bonded to the histidine-57 in the active site and is not reversible bonded to the histidine-57 in the active site and is not reversible

Changes shape of enzymeChanges shape of enzyme Increasing concentration doesn’t Increasing concentration doesn’t

helphelp Poisons DDT, cyanide and antibioticsPoisons DDT, cyanide and antibiotics Means of controlling metabolic Means of controlling metabolic

activity in healthy cellsactivity in healthy cells Thermostat and heaterThermostat and heater

Enzymes vs. catalystsEnzymes vs. catalysts

Enzymes areEnzymes are SpecificSpecific Reaction saturationReaction saturation Speed up 1000 to 1000000 timesSpeed up 1000 to 1000000 times Can be inhibitedCan be inhibited Very sensitive to environmental Very sensitive to environmental

changeschanges

Do questions 13 and 14Do questions 13 and 14

B.8 Nucleic acidsB.8 Nucleic acids

DNA and RNADNA and RNA Information storage of genetics in Information storage of genetics in

the nucleusthe nucleus How did it begin?How did it begin?

DNA must be stableDNA must be stable Contain a codeContain a code Be able to replicateBe able to replicate

Nucleic acid structureNucleic acid structure

Polymers of nucleotidesPolymers of nucleotides Three componentsThree components 1. pentose sugar1. pentose sugar riboseribose

Deoxyribose CDeoxyribose C22 lacks an OH lacks an OH

2. Phosphate group2. Phosphate group

POPO443+3+

3. Nitrogenous base3. Nitrogenous base

Purine adenine (A) quanine (G)Purine adenine (A) quanine (G) Larger 2 fused ringsLarger 2 fused rings

Or pyrimidines smaller one ringOr pyrimidines smaller one ring

DNA basesDNA bases

RNARNA

Uracil replaces thymine one less CHUracil replaces thymine one less CH33

POPO44 connects to the 5 carbon connects to the 5 carbon on the sugar, sugar connects on the sugar, sugar connects

from the 1 carbonfrom the 1 carbon

simplifiedsimplified

Joined together by condensation Joined together by condensation reactionsreactions

Phosphate on the 3 carbon of the Phosphate on the 3 carbon of the adjoining sugaradjoining sugar

Called phosphodiester linksCalled phosphodiester links

polynucleotidespolynucleotides

simplifiedsimplified

Putting it togetherPutting it together

Adenine pairs up with thymine (uracil Adenine pairs up with thymine (uracil in RNA)in RNA)

Cytosine and guinine pair upCytosine and guinine pair up Held together by hydrogen bondsHeld together by hydrogen bonds

Double helixDouble helix

1 turn for each 10 nucleotides1 turn for each 10 nucleotides Each side is upside down to each Each side is upside down to each

otherother AnimationAnimation The dna gameThe dna game

RNARNA

Single strandSingle strand Ribose instead of d-riboseRibose instead of d-ribose Uracil instead of thymineUracil instead of thymine 3 types messenger (mRNA), transfer 3 types messenger (mRNA), transfer

(tRNA), ribosomal (rRNA)(tRNA), ribosomal (rRNA)

transcriptiontranscription

In the nucleus, Strands of DNA In the nucleus, Strands of DNA separate (unzip)separate (unzip)

mRNA copies the code by lining up mRNA copies the code by lining up basesbases

mRNA leaves nucleusmRNA leaves nucleus DNA zips upDNA zips up

translationtranslation

Happens in the ribosomeHappens in the ribosome tRNA pulls in amino acids from the tRNA pulls in amino acids from the

cytoplasm to make proteinscytoplasm to make proteins Codons every 3 nucleotide is the Codons every 3 nucleotide is the

code for 1 amino acidcode for 1 amino acid Activity for building a proteinActivity for building a protein

AnimationAnimation One moreOne more

DNA profilingDNA profiling

Only 0.1% of DNA is different in Only 0.1% of DNA is different in humans humans

3 billion base pairs unique3 billion base pairs unique

stepssteps

Obtain DNA from blood, saliva etc.Obtain DNA from blood, saliva etc. Cut into restriction enzymesCut into restriction enzymes Make multiple copiesMake multiple copies Use gel electrophoresisUse gel electrophoresis Irradiated for a autoradiogramIrradiated for a autoradiogram For identity of victims, suspects, For identity of victims, suspects,

paternity, relationships paternity, relationships

Question 15 Question 15

B.9 RespirationB.9 Respiration

Release of energyRelease of energy Glucose breakdownGlucose breakdown

aerobicaerobic Oxygen presentOxygen present Pyruvate oxidized to COPyruvate oxidized to CO22 and H and H22OO Electron transport carriers-Electron transport carriers-

cytochromes cytochromes animationanimation

Anaerobic Anaerobic

Without oxygenWithout oxygen GlycolysisGlycolysis Glucose into pyruvateGlucose into pyruvate Coenzyme NADCoenzyme NAD++

Forms lactic acidForms lactic acid Only 2% of energy releasedOnly 2% of energy released animationanimation

Electron transport system involves Electron transport system involves FeFe+2 +2 to Feto Fe+3+3

CUCU+1+1 to Cu to Cu+2+2

Cytochrome Cytochrome Cytochrome oxidase passes e- to OCytochrome oxidase passes e- to O22

to make Hto make H22OO

HemoglobbinHemoglobbin

OO22 bound to it bound to it FeFe+2 +2 stays in this statestays in this state Reversible oxy hemoglobbinReversible oxy hemoglobbin

Question 16Question 16 Do the questions on page 541-545 in Do the questions on page 541-545 in

your textbook and 104 in your study your textbook and 104 in your study bookletbooklet