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Organic vs. InorganicOrganic vs. Inorganic All compounds can be separated All compounds can be separated

into two groups: into two groups: InorganicInorganic

• Doesn’t contain carbonDoesn’t contain carbon• Non-livingNon-living• Examples: Oxygen gas, metals, rocks, Examples: Oxygen gas, metals, rocks,

water water OrganicOrganic

• Contains carbonContains carbon• Living (or dead)Living (or dead)• Examples: wood, grass, diamonds, Examples: wood, grass, diamonds,

petroleumpetroleum

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PolymerizationPolymerization

MonomersMonomers One unit of a compoundOne unit of a compound

PolymersPolymers Many monomers combine to make a Many monomers combine to make a

polymerpolymer MacromoleculesMacromolecules

Many large molecules combined Many large molecules combined

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CarbohydratesCarbohydrates Made of C, H, OMade of C, H, O FunctionsFunctions

Main energy source in organismsMain energy source in organisms Structural component in plants (CELLULOSE)Structural component in plants (CELLULOSE)

TypesTypes Sugars Sugars

• gives off energy when broken downgives off energy when broken down• Ex. Sucrose, fructose, glucoseEx. Sucrose, fructose, glucose

Starches Starches • used as a storage molecule for sugarsused as a storage molecule for sugars• Ex. Bread, rice, pasta, cornEx. Bread, rice, pasta, corn

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LipidsLipids Made of C, H, O Made of C, H, O

in the form of glycerol and fatty acid chainsin the form of glycerol and fatty acid chains Commonly called fats, oils, waxesCommonly called fats, oils, waxes FunctionsFunctions

Storage of energyStorage of energy Parts of biological membranesParts of biological membranes Water proof coveringsWater proof coverings Chemical messengers (steroids)Chemical messengers (steroids)

Insoluble in waterInsoluble in water Ex. Lard, butter, oil, hormones, steroids Ex. Lard, butter, oil, hormones, steroids

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Saturated fats (lard) lack double bondsSaturated fats (lard) lack double bonds They are solid at room temperatureThey are solid at room temperature

Fatty acid

Figure 3.8C

Figure 3.8B

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Nucleic acidsNucleic acids Made of C, H, O, N, PMade of C, H, O, N, P Monomers are called Monomers are called

nucleotidesnucleotides Nucleotides are made up Nucleotides are made up

of a 5-carbon sugar, of a 5-carbon sugar, phosphate group and a phosphate group and a nitrogen basenitrogen base

FunctionsFunctions Store hereditary Store hereditary

informationinformation Transmit hereditary Transmit hereditary

informationinformation Two typesTwo types

RNA (ribonucleic acid)RNA (ribonucleic acid) DNA (deoxyribonucleic DNA (deoxyribonucleic

acid)acid)

Phosphate

groupSugar

Figure 3.20A

Nitrogenous

base (A)

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RNA vs DNARNA vs DNA There are THREE main differences There are THREE main differences

between DNA & RNAbetween DNA & RNA The sugarThe sugar

• In DNA its DEOXYribose sugarIn DNA its DEOXYribose sugar• In RNA it’s Ribose sugarIn RNA it’s Ribose sugar

Number of strandsNumber of strands• DNA is usually double strandedDNA is usually double stranded• RNA is ONLY single strandedRNA is ONLY single stranded

Nitrogen BasesNitrogen Bases• DNADNA

• Adenine pairs with ThymineAdenine pairs with Thymine• Guanine pairs with CytosineGuanine pairs with Cytosine

• RNA RNA • Adenine pairs with UracilAdenine pairs with Uracil• Guanine pairs with CytosineGuanine pairs with Cytosine

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ProteinsProteins Made of C, H, O, N (P, S)Made of C, H, O, N (P, S) Monomers are amino acidsMonomers are amino acids

There are 20 different amino There are 20 different amino acids that combine in different acids that combine in different ways to make millions of proteinsways to make millions of proteins

The most diverse The most diverse macromoleculesmacromolecules

FunctionsFunctions Control the rates of chemical Control the rates of chemical

reactions (enzymes)reactions (enzymes) Regulate cell processesRegulate cell processes Used to form bone & musclesUsed to form bone & muscles Transport substances into or out Transport substances into or out

of cellsof cells Help fight diseaseHelp fight disease

Aminogroup

Carboxyl (acid)group

Figure 3.12A

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Figure 3.15, 16

Amino acid

Hydrogen bond

Pleated sheet

Primarystructure

Secondarystructure

Figure 3.17, 18

Polypeptide(single subunitof transthyretin)

Transthyretin, with fouridentical polypeptide subunits

Tertiarystructure

Quaternarystructure

Alpha helix

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EnzymesEnzymes

Reaction pathwaywithout enzyme Activation energy

without enzyme

Activationenergywith enzymeReaction pathway

with enzyme

Reactants

Products

Special PROTEINSSpecial PROTEINS Act as biological CATALYSTS:Act as biological CATALYSTS:

speed up the rate of a chemical reaction by speed up the rate of a chemical reaction by lowering the activation energy of the lowering the activation energy of the reactionreaction

Activation Energy: energy needed to Activation Energy: energy needed to transform reactant substances into product transform reactant substances into product substancessubstances

• Enzymes are specific in the reactions they catalyze (Lock and Key model)

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• They will only catalyze one specific substance, in one direction (a -> b, but not b -> a)

• They are reusable• A substance that an enzyme reacts on is called the

enzyme’s substrate• Only the active site in the enzyme actually binds to

the substrate

• Enzymes end in –ase• Example: amylase, helicase

Factors Affecting Enzyme Factors Affecting Enzyme Activity:Activity:

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• PH• Temperature• Salt concentration

• Enzymes lose their shape easily (denature)

• Shape is very important in enzyme activity!