Chemistry of Life

Matter

MatterMatterMass vs. Weight

Elements and AtomsNucleus

◦Neutrons ◦Protons

Electrons◦Orbital

Isotopes

Compounds Made up of atoms of 2 or more elements

in fixed proportions

Covalent BondsTwo atoms share one or more pairs of

electrons

Ionic BondsIons that have opposite charge are

attracted to each other

EnergyAbility to do work

Many forms

Matter StatesSolid

Liquid

Gas

Chemical Reactions and EnergyOne or more substances change to

produce one or more different substances

Reactants vs. Products

Activation Energy

Redox reactions

Water

WaterPolar molecule – unequal distribution of

charge

Hydrogen bond – weak bond between O and H

Solubility

Water Cohesion

◦Attraction of molecule to itself

◦Surface tension

WaterAdhesion

◦Attraction of molecule to other molecules

◦Water drops on a window

WaterCapillary action

◦Both cohesion and adhesion at work

◦Movement through small tubes

◦Moves against gravity

Properties of WaterCohesion/adhesionSolventResists temperature changesHigh heat of vaporizationExpands when freezes

Solution, Solvent and SoluteMixture in which one of more substances

are uniformly distributed

Solvent◦Substance being dissolved

Solute◦Substance which is doing the dissolving

Acids and BasespH scaleAcids

◦pH below 7; forms H+ ions in waterBases

◦pH ablove 7; forms OH- ions in waterNeutrals

◦pH is 7Buffers

Biochemistry

CarbonOrganic compounds4 e- in outer shell; will bind with 4 other

elements Likes to bond with itselfNumber of bonds

Functional GroupsHydroxyl

Carboxyl

Amino

Phosphate

FormationMonomer vs. Polymer

Condensation Reactions

Hydrolysis Reaction

Energy for LifeAdenosine triphosphate (ATP)

Gives off much energy with Phosphate group is broken off and converted to ADP

ATP ADP + Pi

Organic Compounds Essential for Life

CarbohydratesComposed of C, H, and O in a 1:2:1

Monomers are monosaccharides

-ose suffix

CarbohydratesMonosaccharides

Disaccharides

Polysaccharides

CarbohydratesCarbs in Animals

◦Stored as glycogen in muscles

Carbs in Plants◦Stored as cellulose ◦Found in cell wall of plants

ProteinsComposed of C, H, O, and NMonomers are amino acids20 different amino acids Each amino acid contains the following

◦Central carbon◦Carboxyl group◦Amino group◦R group

Protein StructurePrimary

◦Polypeptide chainSecondary

◦Folds, based upon H bonds◦α helix◦β pleated sheet

Tertiary◦Folds, based upon charge◦3D shape

LipidsComposed of C, H, and OMonomers are glycerol and fatty acids

Saturated

Unsaturated

Nucleic AcidsComposed of C, H, O, N, and PMonomers are nucleotides4 different nucleotides

Enzymes

EnzymeSpecific type of proteinActs as a catalyst for chemical reactionEssential for cell function

Enzymes Molecule acted upon is called SubstrateHighly specific

◦Break down◦Build up

Named for substratesEnd in –ase

EnzymesCategories

◦Hydrolases◦Lyases◦Transferases◦Isomerases◦Oxidoreductases◦Synthetases

Models◦Lock and key◦Induced fit

Factors Affecting EnzymesAmount of substrateTemperaturepH