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Chemistry Comes Chemistry Comes Alive Alive

Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

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Page 1: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Chemistry Comes Chemistry Comes AliveAlive

Page 2: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

The Chemistry of LifeThe Chemistry of Life

Atoms, Ions and MoleculesAtoms, Ions and Molecules Water and MixturesWater and Mixtures Energy and Chemical ReactionsEnergy and Chemical Reactions Organic compoundsOrganic compounds

Page 3: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

MatterMatter

The “stuff” of the universeThe “stuff” of the universe Anything that has mass and takes up Anything that has mass and takes up

spacespace States of matterStates of matter

Solid – has definite shape and volumeSolid – has definite shape and volume Liquid – has definite volume, changeable Liquid – has definite volume, changeable

shapeshape Gas – has changeable shape and volumeGas – has changeable shape and volume

Page 4: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

The Chemical ElementsThe Chemical Elements

Element Element simplest form of matter with unique simplest form of matter with unique

chemical propertieschemical properties

Each element has unique physical and Each element has unique physical and chemical propertieschemical properties Physical properties – those detected with Physical properties – those detected with

our sensesour senses Chemical properties – pertain to the way Chemical properties – pertain to the way

atoms interact with one anotheratoms interact with one another

Page 5: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Major Elements of the Major Elements of the Human BodyHuman Body

98.5% of body weight consists of98.5% of body weight consists of Oxygen (O)Oxygen (O) Carbon (C)Carbon (C) Hydrogen (H)Hydrogen (H) Nitrogen (N)Nitrogen (N)

Page 6: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Lesser and Trace Lesser and Trace Elements of the Human Elements of the Human

BodyBody Lesser elements make up 3.9% of the Lesser elements make up 3.9% of the

body and include:body and include: Calcium (Ca), phosphorus (P), potassium Calcium (Ca), phosphorus (P), potassium

(K), sulfur (S), sodium (Na), chlorine (Cl), (K), sulfur (S), sodium (Na), chlorine (Cl), magnesium (Mg), iodine (I), and iron (Fe)magnesium (Mg), iodine (I), and iron (Fe)

Trace elements make up less than Trace elements make up less than 0.01% of the body0.01% of the body They are required in minute amounts, They are required in minute amounts,

and are found as part of enzymesand are found as part of enzymes

Page 7: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical
Page 8: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Periodic Table of the Periodic Table of the ElementsElements

Atomic number of each elementAtomic number of each element number of protons in its nucleusnumber of protons in its nucleus

Periodic table Periodic table letter symbols of elements arranged by letter symbols of elements arranged by

atomic numberatomic number

http://pearl1.lanl.gov/periodic/default.htm

Page 9: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

AtomicAtomic Structure Structure

Nucleus - center of atom containsNucleus - center of atom contains protons: positive charge, mass of 1 amuprotons: positive charge, mass of 1 amu neutrons: neutral charge, mass of 1 amuneutrons: neutral charge, mass of 1 amu atomic mass = total # of protons + neutronsatomic mass = total # of protons + neutrons

Electron shells Electron shells electrons: negative chargeelectrons: negative charge # of electrons = # of protons, atoms have neutral # of electrons = # of protons, atoms have neutral

chargecharge electrons further from nucleus have higher energyelectrons further from nucleus have higher energy valence electrons are in the outermost shellvalence electrons are in the outermost shell

interact with other atomsinteract with other atoms determine chemical behaviordetermine chemical behavior octet rule - atoms react to obtain a stable number of 8 octet rule - atoms react to obtain a stable number of 8

valence electronsvalence electrons

Page 10: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Bohr Planetary Model of an Bohr Planetary Model of an AtomAtom

Page 11: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Models of Some ElementsModels of Some Elements

p+ represents protons, no represents neutrons

Page 12: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Isotopes and RadioactivityIsotopes and Radioactivity IsotopesIsotopes

elements that differ in the number of neutronselements that differ in the number of neutrons 11H, H, 22H, H, 33HH

extra neutrons result in increased atomic weightextra neutrons result in increased atomic weight ““heavy water”heavy water”

have have nono change in change in chemicalchemical behavior behavior same valence electronssame valence electrons

Atomic weightAtomic weight AverageAverage atomic mass of the mixture of isotopes atomic mass of the mixture of isotopes

of an element found in a sampleof an element found in a sample

Page 13: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Isotopes of HydrogenIsotopes of Hydrogen

Figure 2.3

–radioisotopes decay to stable isotopes releasing radiation–radioisotopes decay to stable isotopes releasing radiation

Page 14: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Radioisotopes and Radioisotopes and RadioactivityRadioactivity

Isotopes Isotopes same chemical same chemical

behavior, differ in behavior, differ in physical behaviorphysical behavior

Radioisotopes Radioisotopes unstable isotopesunstable isotopes

Radioactivity Radioactivity radioisotopes decay radioisotopes decay

to stable isotopes to stable isotopes releasing radiationreleasing radiation

Marie Curie

Page 15: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

High energyHigh energy Ejects electrons from atomsEjects electrons from atoms Destroys molecules and produces free radicalsDestroys molecules and produces free radicals

sources include:sources include: UV light, X rays, nuclear decay (UV light, X rays, nuclear decay (, , , , ))

particle - particle - 2 protons + 2 neutrons can’t penetrate skin2 protons + 2 neutrons can’t penetrate skin

particle -particle - free electron - penetrates skin a few millimetersfree electron - penetrates skin a few millimeters

particle -particle - high energy, penetrating; very dangeroushigh energy, penetrating; very dangerous

Ionizing RadiationIonizing Radiation

Page 16: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Physical half-lifePhysical half-life time for 50% of atoms to decaytime for 50% of atoms to decay 9090Sr - 28 yr.Sr - 28 yr. 4040K - 1.3 billion yearsK - 1.3 billion years

Biological half-lifeBiological half-life time for 50% of atoms to disappear from the bodytime for 50% of atoms to disappear from the body function of decay and physiological clearancefunction of decay and physiological clearance

Cesium 137 - physical half-life -- 30 years Cesium 137 - physical half-life -- 30 years - biological half-life -- 17 - biological half-life -- 17

daysdays

Radiation exposureRadiation exposure background radiationbackground radiation

radon gas from decay of uranium in graniteradon gas from decay of uranium in granite cosmic rayscosmic rays

Ionizing Radiation 2Ionizing Radiation 2

Page 17: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Molecules and Chemical Molecules and Chemical BondsBonds

MoleculesMolecules two or more atoms of same element two or more atoms of same element

covalently bondedcovalently bonded

CompoundsCompounds two or more atoms of different elements two or more atoms of different elements

covalently bondedcovalently bonded

Molecular formula Molecular formula itemizes each element present and its itemizes each element present and its

quantityquantity Structural formulaStructural formula

shows arrangement of atomsshows arrangement of atoms needed to show structural isomersneeded to show structural isomers

Page 18: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Concentration of Concentration of SolutionsSolutions

Percent, or parts per 100 partsPercent, or parts per 100 parts Molarity, or moles per liter (Molarity, or moles per liter (MM))

Mole – Avagadro’s number of moleculesMole – Avagadro’s number of molecules 6.02 X 106.02 X 1023 23

A mole of an element or compound is A mole of an element or compound is equal to its atomic or molecular equal to its atomic or molecular weight (sum of atomic weights) in weight (sum of atomic weights) in gramsgrams

Page 19: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Types of Chemical BondsTypes of Chemical Bonds

Ionic Ionic Covalent Covalent HydrogenHydrogen

Page 20: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Chemical BondsChemical Bonds Electron shells, or energy levels, surround Electron shells, or energy levels, surround

the nucleus of an atomthe nucleus of an atom Bonds are formed using the electrons in Bonds are formed using the electrons in

the outermost energy levelthe outermost energy level Valence shell – outermost energy level Valence shell – outermost energy level

containing chemically active electronscontaining chemically active electrons Octet rule – except for the first shell which Octet rule – except for the first shell which

is full with two electrons, atoms interact in is full with two electrons, atoms interact in a manner to have eight electrons in their a manner to have eight electrons in their valence shellvalence shell

Page 21: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Chemically Inert Chemically Inert ElementsElements Inert elements have their outermost energy level Inert elements have their outermost energy level

fully occupied by electronsfully occupied by electrons

Figure 2.4a

Page 22: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Chemically Reactive Chemically Reactive ElementsElements

Reactive Reactive elements do elements do not have their not have their outermost outermost energy level energy level fully occupied fully occupied by electronsby electrons

Figure 2.4b

Page 23: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Ions - carry a charge, unequal Ions - carry a charge, unequal numbers of protons and electronsnumbers of protons and electrons

Ionization - Ionization - transfer of transfer of electrons from one electrons from one atom to another (atom to another ( stability of valence stability of valence shell)shell)

IonsIons

Page 24: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Anion - atom gained electron, net negative chargeAnion - atom gained electron, net negative charge Cation - atom lost an electron, net positive chargeCation - atom lost an electron, net positive charge

Anions and CationsAnions and Cations

Page 25: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Ionic BondsIonic Bonds

Attraction of oppositely charged ions to each other Attraction of oppositely charged ions to each other forms an ionic bond - no sharing of electronsforms an ionic bond - no sharing of electrons

Ionic bonds are weak and dissociate in waterIonic bonds are weak and dissociate in water These compounds tend to form crystals...These compounds tend to form crystals...

Page 26: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Formation of an Ionic Formation of an Ionic BondBond

Figure 2.5a

Page 27: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Covalent BondsCovalent Bonds Formed by sharing Formed by sharing

valence electronsvalence electrons Types of covalent Types of covalent

bondsbonds single covalent single covalent

bondbond

double covalent double covalent bondbond

Triple covalent Triple covalent bondbond

Page 28: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Polar and Nonpolar Polar and Nonpolar MoleculesMolecules

Electrons shared equally between Electrons shared equally between atoms produce nonpolar moleculesatoms produce nonpolar molecules

Unequal sharing of electrons Unequal sharing of electrons produces polar moleculesproduces polar molecules

Atoms with six or seven valence shell Atoms with six or seven valence shell electrons are electronegativeelectrons are electronegative

Atoms with one or two valence shell Atoms with one or two valence shell electrons are electropositiveelectrons are electropositive

Page 29: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Figure 2.8

Comparison of Ionic, Polar Comparison of Ionic, Polar Covalent, and Nonpolar Covalent, and Nonpolar

Covalent BondsCovalent Bonds

Page 30: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Hydrogen BondsHydrogen Bonds

Weakest of the bondsWeakest of the bonds Attraction between polar molecules – no Attraction between polar molecules – no

sharing of electronssharing of electrons Greatest physiological importanceGreatest physiological importance

properties of waterproperties of water shapes of complex moleculesshapes of complex molecules

proteins, DNAproteins, DNA

Page 31: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Hydrogen Bonding in WaterHydrogen Bonding in Water

Page 32: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

The Chemistry of LifeThe Chemistry of Life

Atoms, Ions and MoleculesAtoms, Ions and Molecules Water and MixturesWater and Mixtures Energy and Chemical ReactionsEnergy and Chemical Reactions Organic compoundsOrganic compounds

Page 33: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Adhesion and CohesionAdhesion and Cohesion

Adhesion - attraction between one Adhesion - attraction between one substance and another substancesubstance and another substance

Cohesion - attraction between one Cohesion - attraction between one substance and itselfsubstance and itself water is very cohesive due to hydrogen water is very cohesive due to hydrogen

bondsbonds Surface tension Surface tension

elastic surface film caused by the attraction elastic surface film caused by the attraction of molecules at the surface from those of molecules at the surface from those belowbelow

Page 34: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Thermal Stability of Thermal Stability of WaterWater

Heat capacityHeat capacity: amount of heat required to : amount of heat required to raise the temperature of 1g of a raise the temperature of 1g of a substancesubstance by 1°Cby 1°C

CalorieCalorie: amount of heat required to raise the : amount of heat required to raise the temperature of 1g of temperature of 1g of waterwater by 1°C by 1°C

Water stabilizes internal temperature of the Water stabilizes internal temperature of the bodybody high heat capacityhigh heat capacity

its hydrogen bonds inhibit increased temperature its hydrogen bonds inhibit increased temperature (molecular motion) caused by increased heat(molecular motion) caused by increased heat

effective coolanteffective coolant 1 ml of perspiration removes 500 calories from the body 1 ml of perspiration removes 500 calories from the body

Page 35: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Properties of WaterProperties of Water

Reactivity – is an important part of Reactivity – is an important part of hydrolysis and dehydration synthesis hydrolysis and dehydration synthesis reactionsreactions

Cushioning – resilient cushion around Cushioning – resilient cushion around certain body organscertain body organs

InterActive Physiology®: Fluid, Electrolyte, and Acid/Base Balance: Introduction to Body FluidsPLAYPLAY

Page 36: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Mixtures and SolutionsMixtures and Solutions

Mixtures – two or more components Mixtures – two or more components physically intermixed (not chemically physically intermixed (not chemically bonded)bonded)

Solutions – homogeneous mixtures of Solutions – homogeneous mixtures of componentscomponents Solvent – substance present in greatest Solvent – substance present in greatest

amountamount Solute – substance(s) present in smaller Solute – substance(s) present in smaller

amountsamounts

Page 37: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

SolvencySolvency

Solvency - ability to dissolve matterSolvency - ability to dissolve matter Hydrophilic - charged substances that Hydrophilic - charged substances that

dissolve easily in waterdissolve easily in water Hydrophobic - neutral substances that Hydrophobic - neutral substances that

do not easily dissolve in waterdo not easily dissolve in water Water is the universal solvent, important Water is the universal solvent, important

for metabolic reactions and transport of for metabolic reactions and transport of substancessubstances

Page 38: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Water as a SolventWater as a Solvent

Water molecules overpower the ionic bond above Water molecules overpower the ionic bond above between Nabetween Na++ClCl- - by forming hydration spheres. by forming hydration spheres.

Note orientation of water molecules: negative pole Note orientation of water molecules: negative pole faces Nafaces Na++, positive pole faces Cl, positive pole faces Cl- -

Page 39: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

MixturesMixtures

Substances that Substances that are physically are physically blended but not blended but not chemically chemically combinedcombined

SolutionsSolutions ColloidsColloids SuspensionsSuspensions

Page 40: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

SolutionsSolutions

Solute < 1nmSolute < 1nm pass through pass through

membranesmembranes TransparentTransparent e.g. copper sulfate e.g. copper sulfate

solutionsolution

Page 41: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

ColloidsColloids

Particles 1 to Particles 1 to 100nm100nm to large to pass to large to pass

through through membranesmembranes

CloudyCloudy e.g. milk proteine.g. milk protein

Page 42: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

SuspensionsSuspensions

Particles >100nmParticles >100nm Cloudy or opaqueCloudy or opaque Separate on Separate on

standingstanding e.g. blood cellse.g. blood cells

Page 43: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Measures of Measures of ConcentrationConcentration

Weight per VolumeWeight per Volume weight of solute in a given volume of weight of solute in a given volume of

solutionsolution e.g. IV saline contains 8.5 g/L NaCle.g. IV saline contains 8.5 g/L NaCl

PercentagesPercentages weight or volume of solute in solutionweight or volume of solute in solution

e.g. IV D5W (5% w/v dextrose in distilled water)e.g. IV D5W (5% w/v dextrose in distilled water) 5 grams of dextrose in add 100ml water5 grams of dextrose in add 100ml water

MolarityMolarity number of moles of solute/liter in solutionnumber of moles of solute/liter in solution physiologic effects of a chemical based on physiologic effects of a chemical based on

the number of molecules in solutionthe number of molecules in solution

Page 44: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

SaltsSalts

Inorganic compoundsInorganic compounds Contain cations other than HContain cations other than H++ and and

anions other than OHanions other than OH––

Are electrolytes; they conduct Are electrolytes; they conduct electrical currentselectrical currents

Page 45: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Acids and BasesAcids and Bases

Acids release HAcids release H+ + and are therefore and are therefore proton donorsproton donors

HCl HCl H H+ + + Cl+ Cl – –

Bases release OHBases release OH–– and are proton and are proton acceptorsacceptors

NaOH NaOH Na Na+ + + OH+ OH––

Page 46: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Acid-Base Concentration Acid-Base Concentration (pH)(pH)

Acidic solutions have higher HAcidic solutions have higher H++ concentration and therefore a lower concentration and therefore a lower pHpH

Alkaline solutions have lower HAlkaline solutions have lower H+ +

concentration and therefore a higher concentration and therefore a higher pHpH

Neutral solutions have equal HNeutral solutions have equal H+ + and and OHOH–– concentrations concentrations

Page 47: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

pHpH pH - based on the molarity of HpH - based on the molarity of H++ on a on a

logarithmic scalelogarithmic scale pH = -log [HpH = -log [H++]] for molarity of Hfor molarity of H++ = 10 = 1000,10,10-1-1,10,10-2-2,etc.,etc.

pH = - log [10pH = - log [1000] = 0, - log [10] = 0, - log [10-1-1] = 1, etc.] = 1, etc. a change of one number on the pH scale a change of one number on the pH scale

therefore represents a 10 fold change in therefore represents a 10 fold change in HH++ concentration concentration

Our body uses buffers to resist any Our body uses buffers to resist any change in pHchange in pH

Page 48: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

pH ScalepH Scale

Page 49: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

BuffersBuffers

Systems that resist abrupt and large Systems that resist abrupt and large swings in the pH of body fluidsswings in the pH of body fluids

Carbonic acid-bicarbonate systemCarbonic acid-bicarbonate system Carbonic acid dissociates, reversibly Carbonic acid dissociates, reversibly

releasing bicarbonate ions and protonsreleasing bicarbonate ions and protons The chemical equilibrium between The chemical equilibrium between

carbonic acid and bicarbonate resists pH carbonic acid and bicarbonate resists pH changes in the bloodchanges in the blood

InterActive Physiology®: Fluid, Electrolyte, and Acid/Base Balance: Acid/Base HomeostasisPLAYPLAY

Page 50: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

The Chemistry of LifeThe Chemistry of Life

Atoms, Ions and MoleculesAtoms, Ions and Molecules Water and MixturesWater and Mixtures Energy and Chemical ReactionsEnergy and Chemical Reactions Organic compoundsOrganic compounds

Page 51: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Work and EnergyWork and Energy Energy - the capacity to do workEnergy - the capacity to do work Kinetic energy - energy of motionKinetic energy - energy of motion Potential energy- inherent energy Potential energy- inherent energy

due to an objects position or due to an objects position or internal stateinternal state

Chemical energy - potential energy Chemical energy - potential energy stored in the molecular bondsstored in the molecular bonds

Electromagnetic energy - kinetic Electromagnetic energy - kinetic energy of photons: energy of photons: light, infrared, UV, X rays + light, infrared, UV, X rays + rays rays

Page 52: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Chemical ReactionsChemical Reactions

Occur when chemical bonds are Occur when chemical bonds are formed, rearranged, or brokenformed, rearranged, or broken

Are written in symbolic form using Are written in symbolic form using chemical equationschemical equations

Chemical equations contain:Chemical equations contain: Number and type of reacting Number and type of reacting

substances, and products producedsubstances, and products produced Relative amounts of reactants and Relative amounts of reactants and

productsproducts

Page 53: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Examples of Chemical Examples of Chemical ReactionsReactions

Page 54: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Patterns of Chemical Patterns of Chemical ReactionsReactions

Combination reactions:Combination reactions: Synthesis Synthesis reactions which always involve bond reactions which always involve bond formationformation

A + B A + B AB AB

Decomposition reactions: Molecules are Decomposition reactions: Molecules are broken down into smaller molecules broken down into smaller molecules

AB AB A + B A + B

Exchange reactions: Bonds are both made Exchange reactions: Bonds are both made and brokenand broken

AB + C AB + C AC + B AC + B

Page 55: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Energy Flow in Chemical Energy Flow in Chemical ReactionsReactions

Exergonic reactions – reactions that Exergonic reactions – reactions that release energyrelease energy

Endergonic reactions – reactions Endergonic reactions – reactions whose products contain more whose products contain more potential energy than did its potential energy than did its reactantsreactants

Page 56: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

MetabolismMetabolism

All the chemical reactions of the bodyAll the chemical reactions of the body CatabolismCatabolism

energy releasing (exergonic) energy releasing (exergonic) decomposition reactionsdecomposition reactions

AnabolismAnabolism energy releasing (endergonic) synthesis energy releasing (endergonic) synthesis

reactionsreactions

Page 57: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Reaction RatesReaction Rates

Basis for chemical reactions is molecular Basis for chemical reactions is molecular motion and collisionsmotion and collisions

Reaction Rates affected by:Reaction Rates affected by: concentrationconcentration

more concentrated, more collisions, faster rxmore concentrated, more collisions, faster rx temperaturetemperature

higher temperature, greater collision force, faster rxhigher temperature, greater collision force, faster rx catalystscatalysts

speed up reactions without permanent change to speed up reactions without permanent change to itselfitself

biological catalysts are enzymesbiological catalysts are enzymes

Page 58: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Oxidation-Reduction Oxidation-Reduction (Redox) Reactions(Redox) Reactions

Reactants losing electrons are Reactants losing electrons are electron donors and are oxidizedelectron donors and are oxidized

Reactants taking up electrons are Reactants taking up electrons are electron acceptors and become electron acceptors and become reducedreduced

Page 59: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Energy Flow in Chemical Energy Flow in Chemical ReactionsReactions

Exergonic reactions – reactions that Exergonic reactions – reactions that release energyrelease energy

Endergonic reactions – reactions Endergonic reactions – reactions whose products contain more whose products contain more potential energy than did its potential energy than did its reactantsreactants

Page 60: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

The Chemistry of LifeThe Chemistry of Life

Atoms, Ions and MoleculesAtoms, Ions and Molecules Water and MixturesWater and Mixtures Energy and Chemical ReactionsEnergy and Chemical Reactions Organic compoundsOrganic compounds

Page 61: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Organic CompoundsOrganic Compounds

Molecules unique to living systems Molecules unique to living systems contain carbon and hence are contain carbon and hence are organic compoundsorganic compounds

They include:They include: CarbohydratesCarbohydrates LipidsLipids ProteinsProteins Nucleic AcidsNucleic Acids

Page 62: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Organic Molecules: Organic Molecules: CarbonCarbon

Bonds readily with other carbon atoms, Bonds readily with other carbon atoms, hydrogen, oxygen, nitrogen, sulfur hydrogen, oxygen, nitrogen, sulfur needs 4 more valence electronsneeds 4 more valence electrons

Can form rings or long carbon chains Can form rings or long carbon chains that serve as the backbone for organic that serve as the backbone for organic moleculesmolecules

Page 63: Chemistry Comes Alive. The Chemistry of Life Atoms, Ions and Molecules Atoms, Ions and Molecules Water and Mixtures Water and Mixtures Energy and Chemical

Groups of atoms Groups of atoms attach to carbon attach to carbon backbonebackbone

Determine the Determine the properties of organic properties of organic moleculesmolecules

Functional Groups Functional Groups

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Monomers and PolymersMonomers and Polymers Monomers Monomers

subunits of macromoleculessubunits of macromolecules DNA has 4 different monomers (nucleotides)DNA has 4 different monomers (nucleotides) proteins have 20 different monomers (amino proteins have 20 different monomers (amino

acids)acids) PolymersPolymers

series of monomers bonded togetherseries of monomers bonded together PolymerizationPolymerization

the bonding of monomers together to form the bonding of monomers together to form a polymera polymer

caused by a reaction called dehydration caused by a reaction called dehydration synthesissynthesis

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Monomers and PolymersMonomers and Polymers Monomers Monomers

subunits of macromoleculessubunits of macromolecules DNA has 4 different monomers (nucleotides)DNA has 4 different monomers (nucleotides) proteins have 20 different monomers (amino proteins have 20 different monomers (amino

acids)acids) PolymersPolymers

series of monomers bonded togetherseries of monomers bonded together PolymerizationPolymerization

the bonding of monomers together to form the bonding of monomers together to form a polymera polymer

caused by a reaction called dehydration caused by a reaction called dehydration synthesissynthesis

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HydrolysisHydrolysis Splitting a polymer (lysis) by the addition Splitting a polymer (lysis) by the addition

of a water molecule (hydro)of a water molecule (hydro) Digestion consists of hydrolysis reactionsDigestion consists of hydrolysis reactions

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CarbohydratesCarbohydrates

Figure 2.13a

Contain carbon, hydrogen, and oxygenContain carbon, hydrogen, and oxygen Their major function is to supply a Their major function is to supply a

source of cellular foodsource of cellular food ExamplesExamples::

Monosaccharides or simple sugarsMonosaccharides or simple sugars

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Organic Molecules: Organic Molecules: CarbohydratesCarbohydrates

Hydrophilic organic moleculeHydrophilic organic molecule General formula General formula

(CH(CH22O)O)n n , n = number of carbon atoms, n = number of carbon atoms

for glucose, n = 6, so formula is Cfor glucose, n = 6, so formula is C66HH1212OO66

Names of carbohydratesNames of carbohydrates word root word root saccharsacchar- or the suffix -- or the suffix -ose ose often often

usedused monosaccharide or glucosemonosaccharide or glucose

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MonosaccharidesMonosaccharides Simplest carbohydratesSimplest carbohydrates General formula is CGeneral formula is C66HH1212OO66

structural isomersstructural isomers

Three major monosaccharidesThree major monosaccharides glucose, galactose and fructoseglucose, galactose and fructose mainly produced by digestion of mainly produced by digestion of

complex carbohydratescomplex carbohydrates

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DisaccharidesDisaccharides

Pairs of Pairs of monosaccharidesmonosaccharides

Three major Three major disaccharidesdisaccharides sucrose sucrose

glucose + fructoseglucose + fructose lactoselactose

glucose + galactoseglucose + galactose maltosemaltose

glucose + glucoseglucose + glucose

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PolysaccharidesPolysaccharides Starch, cellulose and glycogen Starch, cellulose and glycogen

long chains of glucose form these polysaccharideslong chains of glucose form these polysaccharides Starch produced by plants is digested by amylaseStarch produced by plants is digested by amylase Cellulose gives structure to plants, fiber to our Cellulose gives structure to plants, fiber to our

dietdiet

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PolysaccharidesPolysaccharides Glycogen is an energy storage Glycogen is an energy storage

polysaccharide produced by animals polysaccharide produced by animals Liver cells synthesize glycogen after a Liver cells synthesize glycogen after a

meal to maintain blood glucose levelsmeal to maintain blood glucose levels

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Carbohydrate Carbohydrate FunctionsFunctions

Source of energySource of energy Conjugated carbohydratesConjugated carbohydrates

glycolipids glycolipids external surface of cell membraneexternal surface of cell membrane

glycoproteinsglycoproteins external surface of cell membraneexternal surface of cell membrane mucus of respiratory and digestive tractsmucus of respiratory and digestive tracts

proteoglycansproteoglycans carbohydrate component dominantcarbohydrate component dominant cell adhesion, gelatinous filler of tissues (eye) cell adhesion, gelatinous filler of tissues (eye)

and lubricates jointsand lubricates joints

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LipidsLipids

Contain C, H, and O, but the Contain C, H, and O, but the proportion of oxygen in lipids is less proportion of oxygen in lipids is less than in carbohydratesthan in carbohydrates

Examples:Examples: Neutral fats or triglyceridesNeutral fats or triglycerides PhospholipidsPhospholipids SteroidsSteroids EicosanoidsEicosanoids

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Fatty AcidsFatty Acids

Chain of usually 4 to 24 carbon atomsChain of usually 4 to 24 carbon atoms

Carboxyl (acid) groupCarboxyl (acid) group on one end and on one end and a a methyl groupmethyl group on the other on the other

Polymers of two-carbon Polymers of two-carbon acetylacetyl groups groups

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Fatty AcidsFatty Acids Saturated fatty acid - carbon atoms Saturated fatty acid - carbon atoms

saturated with hydrogen saturated with hydrogen Unsaturated fatty acid - contains C=C Unsaturated fatty acid - contains C=C

bonds that could bond more hydrogen bonds that could bond more hydrogen

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Fatty AcidsFatty Acids Saturated fatty acid - carbon atoms Saturated fatty acid - carbon atoms

saturated with hydrogen saturated with hydrogen Unsaturated fatty acid - contains C=C Unsaturated fatty acid - contains C=C

bonds that could bond more hydrogen bonds that could bond more hydrogen

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Triglyceride Synthesis Triglyceride Synthesis (2)(2)

Triglycerides called neutral fatsTriglycerides called neutral fats fatty acids bond with their carboxyl ends, therefore fatty acids bond with their carboxyl ends, therefore

no longer acidicno longer acidic

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TriglyceridesTriglycerides

Hydrolysis of fats occurs by lipase Hydrolysis of fats occurs by lipase enzymeenzyme

Triglycerides at room temperatureTriglycerides at room temperature liquid called oils, often polyunsaturated fats liquid called oils, often polyunsaturated fats

from plantsfrom plants solid called fat, saturated fats from animalssolid called fat, saturated fats from animals

Function - energy storageFunction - energy storage also insulation and shock absorption for also insulation and shock absorption for

organsorgans

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PhospholipidsPhospholipids

Amphiphilic characterAmphiphilic character Hydrophobic “tails” similar to neutral Hydrophobic “tails” similar to neutral

fats with two fatty acids attached to fats with two fatty acids attached to glycerolglycerol

Hydrophilic “head” differs from neutral Hydrophilic “head” differs from neutral fat with the third fatty acid replaced with fat with the third fatty acid replaced with a phosphate group attached to other a phosphate group attached to other functional groupsfunctional groups

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A Phospholipid - A Phospholipid - LecithinLecithin

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SteroidsSteroids

CholesterolCholesterol other steroids derive from cholesterolother steroids derive from cholesterol

cortisol, progesterone, estrogens, cortisol, progesterone, estrogens, testosterone and bile acidstestosterone and bile acids

required for proper nervous system required for proper nervous system function and is an important component function and is an important component of cell membranes of cell membranes

produced only by animalsproduced only by animals 85% naturally produced by our body 85% naturally produced by our body only 15% derived from our dietonly 15% derived from our diet

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EicosanoidsEicosanoids Derived from arachidonic acid (a fatty acid)Derived from arachidonic acid (a fatty acid) Function as chemical signals between cellsFunction as chemical signals between cells Includes prostaglandins Includes prostaglandins

role in inflammation, blood clotting, hormone action, role in inflammation, blood clotting, hormone action, labor contractions, control of blood vessel diameterlabor contractions, control of blood vessel diameter

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CholesterolCholesterol All steroids have this 4 ringed structure All steroids have this 4 ringed structure

with variations in the functional groups with variations in the functional groups and location of double bondsand location of double bonds

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Representative Lipids Representative Lipids Found in the BodyFound in the Body

Neutral fats – found in subcutaneous tissue Neutral fats – found in subcutaneous tissue and around organsand around organs

Phospholipids – chief component of cell Phospholipids – chief component of cell membranesmembranes

Steroids – cholesterol, bile salts, vitamin D, Steroids – cholesterol, bile salts, vitamin D, sex hormones, and adrenal cortical hormonessex hormones, and adrenal cortical hormones

Fat-soluble vitamins – vitamins A, E, and KFat-soluble vitamins – vitamins A, E, and K Eicosanoids – prostaglandins, leukotriens, Eicosanoids – prostaglandins, leukotriens,

and thromboxanesand thromboxanes Lipoproteins – transport fatty acids and Lipoproteins – transport fatty acids and

cholesterol in the bloodstream cholesterol in the bloodstream

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Polymer of amino acidsPolymer of amino acids

Organic Molecules: Organic Molecules: ProteinsProteins

20 amino acids20 amino acids identical except for -R identical except for -R

group attached to central group attached to central carboncarbon

amino acid properties amino acid properties determined by -R groupdetermined by -R group

The amino acids in a The amino acids in a protein determine its protein determine its structure and functionstructure and function

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Amino AcidsAmino Acids

Building blocks of protein, containing Building blocks of protein, containing an amino group and a carboxyl groupan amino group and a carboxyl group

Amino acid structureAmino acid structure

InterActive Physiology®: Fluid, Electrolyte, and Acid/Base Balance: Introduction to Body FluidsPLAYPLAY

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Amino AcidsAmino Acids

Figure 2.15a-c

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Amino AcidsAmino Acids

Figure 2.15d, e

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PeptidesPeptides

A polymer of 2 or more amino acidsA polymer of 2 or more amino acids Named for the number of amino Named for the number of amino

acids they containacids they contain dipeptides have 2, tripeptides have 3dipeptides have 2, tripeptides have 3 oligopeptides have fewer than 10 to 15 oligopeptides have fewer than 10 to 15 polypeptides have more than 15polypeptides have more than 15 proteins have more than 100proteins have more than 100

Dehydration synthesis creates a Dehydration synthesis creates a peptide bond that joins amino acidspeptide bond that joins amino acids

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Dipeptide SynthesisDipeptide Synthesis

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ProteinProtein

Figure 2.16

Macromolecules composed of Macromolecules composed of combinations of 20 types of amino acids combinations of 20 types of amino acids bound together with peptide bondsbound together with peptide bonds

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Structural Levels of Structural Levels of ProteinsProteins

Primary – amino acid sequencePrimary – amino acid sequence Secondary – alpha helices or beta Secondary – alpha helices or beta

pleated sheetspleated sheets

Chemistry of Life: Proteins: Secondary StructurePLAYPLAY

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Structural Levels of Structural Levels of ProteinsProteins

Tertiary – superimposed folding of Tertiary – superimposed folding of secondary structuressecondary structures

Quaternary – polypeptide chains Quaternary – polypeptide chains linked together in a specific mannerlinked together in a specific manner

Chemistry of Life: Proteins: Quaternary StructurePLAYPLAY

Chemistry of Life: Proteins: Tertiary StructurePLAYPLAY

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Fibrous and Globular Fibrous and Globular ProteinsProteins

Fibrous proteinsFibrous proteins Extended and strandlike proteins Extended and strandlike proteins Examples: keratin, elastin, collagen, and Examples: keratin, elastin, collagen, and

certain contractile fiberscertain contractile fibers Globular proteins Globular proteins

Compact, spherical proteins with tertiary Compact, spherical proteins with tertiary and quaternary structuresand quaternary structures

Examples: antibodies, hormones, and Examples: antibodies, hormones, and enzymesenzymes

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Protein DenuaturationProtein Denuaturation

Figure 2.18a

Reversible Reversible unfolding of unfolding of proteins proteins due to due to drops in pH drops in pH and/or and/or increased increased temperaturtemperaturee

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Protein DenuaturationProtein Denuaturation

Figure 2.18b

Irreversibly denatured proteins cannot refold and are Irreversibly denatured proteins cannot refold and are formed by extreme pH or temperature changesformed by extreme pH or temperature changes

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Characteristics of Characteristics of EnzymesEnzymes

Most are globular proteins that act as Most are globular proteins that act as biological catalystsbiological catalysts

Holoenzymes consist of an apoenzyme Holoenzymes consist of an apoenzyme (protein) and a cofactor (usually an ion)(protein) and a cofactor (usually an ion)

Enzymes are chemically specificEnzymes are chemically specific Frequently named for the type of Frequently named for the type of

reaction they catalyzereaction they catalyze Enzyme names usually end in -Enzyme names usually end in -asease Lower activation energy Lower activation energy

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Characteristics of EnzymesCharacteristics of Enzymes

Figure 2.19

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Mechanism of Enzyme Mechanism of Enzyme ActionAction

Enzyme binds with substrateEnzyme binds with substrate Product is formed at a lower activation Product is formed at a lower activation

energyenergy Product is releasedProduct is released

How Enzymes WorkPLAYPLAY

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Nucleic AcidsNucleic Acids

(C), thymine (T), and uracil (U) Composed (C), thymine (T), and uracil (U) Composed of carbon, oxygen, hydrogen, nitrogen, of carbon, oxygen, hydrogen, nitrogen, and phosphorusand phosphorus

Their structural unit, the nucleotide, is Their structural unit, the nucleotide, is composed of N-containing base, a pentose composed of N-containing base, a pentose sugar, and a phosphate groupsugar, and a phosphate group

Five nitrogen bases contribute to Five nitrogen bases contribute to nucleotide structure – adenine (A), nucleotide structure – adenine (A), guanine (G), cytosine guanine (G), cytosine

Two major classes – DNA and RNATwo major classes – DNA and RNA

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Deoxyribonucleic Acid Deoxyribonucleic Acid (DNA)(DNA)

Double-stranded helical molecule Double-stranded helical molecule found in the nucleus of the cellfound in the nucleus of the cell

Replicates itself before the cell Replicates itself before the cell divides, ensuring genetic continuitydivides, ensuring genetic continuity

Provides instructions for protein Provides instructions for protein synthesissynthesis

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Structure of DNAStructure of DNA

Figure 2.21a

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Structure of DNAStructure of DNA

Figure 2.21b

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Ribonucleic Acid (RNA)Ribonucleic Acid (RNA)

Single-stranded molecule found in Single-stranded molecule found in both the nucleus and the cytoplasm both the nucleus and the cytoplasm of a cellof a cell

Uses the nitrogenous base uracil Uses the nitrogenous base uracil instead of thymineinstead of thymine

Three varieties of RNA: messenger Three varieties of RNA: messenger RNA, transfer RNA, and ribosomal RNA, transfer RNA, and ribosomal RNARNA

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Adenosine Triphosphate Adenosine Triphosphate (ATP)(ATP)

Source of immediately usable energy Source of immediately usable energy for the cellfor the cell

Adenine-containing RNA nucleotide Adenine-containing RNA nucleotide with three phosphate groupswith three phosphate groups

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Adenosine Triphosphate Adenosine Triphosphate (ATP)(ATP)

Figure 2.22

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How ATP Drives Cellular How ATP Drives Cellular WorkWork

Figure 2.23