organic molecules of life
DESCRIPTION
Organic Molecules of Life. Organic molecules :. are compounds created by living organisms contain the elements carbon and hydrogen. Carbon atoms:. need four electrons to fill their outer electron shell Must form four bonds with other elements. These are covalent bonds. - PowerPoint PPT PresentationTRANSCRIPT
Organic Molecules of LifeOrganic Molecules of Life
Organic molecules :Organic molecules :
are compounds created by are compounds created by living organismsliving organisms
contain the elements contain the elements carbon and hydrogencarbon and hydrogen
Carbon atoms:Carbon atoms: need four electrons to fill their need four electrons to fill their
outer electron shell outer electron shell
Must form four bonds with Must form four bonds with other elements. other elements.
These are covalent bonds.These are covalent bonds.
Most often bond with Most often bond with Hydrogen, Oxygen, Nitrogen, Hydrogen, Oxygen, Nitrogen, Phosphorus, Sulfur, and other Phosphorus, Sulfur, and other
Carbon atomsCarbon atoms
6 P
6 N
These can include:These can include: Single bonds Single bonds
(one electron shared)(one electron shared)
Double bonds Double bonds (two electrons shared)(two electrons shared)
Or triple bonds Or triple bonds (three electrons shared)(three electrons shared)
Carbon Atoms:Carbon Atoms:
These chains can be:
Can bond with other atoms of carbon to form long chains
Straight
Branched
Rings
IsomersIsomers
Molecules with the Molecules with the same formulasame formula
Atoms are arranged Atoms are arranged differentlydifferently
Carbons are Carbons are branched in various branched in various waysways
Functional groups:Functional groups: Are special groups of atoms that Are special groups of atoms that
stay together and act as a single stay together and act as a single unit unit
can bond with the carbon chains can bond with the carbon chains determine how the entire determine how the entire
molecule will react. molecule will react.
The functional groups The functional groups you need to know are:you need to know are:
Hydroxyl GroupHydroxyl Group
•one oxygen and one hydrogen
• usually written as
-OH
Oxygen
Hydrogen
Carboxyl GroupCarboxyl Group one carbon with a one carbon with a
double bond to an double bond to an oxygen AND a single oxygen AND a single bond to a hydroxyl bond to a hydroxyl group group
usually written as usually written as COOH or COOH or
O=C–OHO=C–OHCreates an organic Creates an organic
acid (carboxylic)acid (carboxylic)
Carbon
Oxygen
Oxygen
Hydrogen
Amino GroupAmino Group
one nitrogen one nitrogen bonded to two bonded to two hydrogenhydrogen
usually written usually written as NHas NH22 or or
H–N–HH–N–H
Nitrogen
Hydrogen
Hydrogen
Phosphate Group:Phosphate Group:
One phosphorus bonded to two hydroxyl One phosphorus bonded to two hydroxyl groups, and two other oxygens (one has a groups, and two other oxygens (one has a double bond)double bond)
Usually written as –P orUsually written as –P or OHOH
O P OO P O
OHOH
Phosphorus
Biological Biological molecules molecules
can be can be made up of made up of thousands thousands of atomsof atoms
These large molecules These large molecules are built from basic are built from basic
units called units called
monomersmonomers..
One monomer
The monomers are linked The monomers are linked together to form the large together to form the large
molecules called molecules called
polymers.polymers.
Polymer – chain of repeating monomer units
Making and Breaking Polymer Making and Breaking Polymer BondsBonds
When two monomers are put together to form larger molecules, a water molecule is created.
Monomers
Polymer
This process is called:This process is called:
(Dehydration means to lose water (Dehydration means to lose water
Synthesis means to build or put Synthesis means to build or put things together)things together)
Dehydration Synthesis.Dehydration Synthesis.
When polymers are broken apart, it is done by adding a water molecule.
This is called
Hydrolysis
(hydro- for water, -lysis for breaking apart)
Types of Organic MoleculesTypes of Organic Molecules
There are four categories of organic There are four categories of organic molecules in organisms:molecules in organisms:
CarbohydratesCarbohydrates
LipidsLipids
ProteinsProteins
Nucleic acidsNucleic acids
CarbohydratesCarbohydrates
What are Carbohydrates?What are Carbohydrates?
Organic compoundsOrganic compoundsCommonly called starches and Commonly called starches and
sugarssugarsUsed as:Used as:
An energy sourceAn energy sourceEnergy storageEnergy storageCellular structures Cellular structures
Chemical CompositionChemical CompositionContains only three elements:Contains only three elements:
CarbonCarbonHydrogenHydrogenOxygenOxygen
Ratio of hydrogen to oxygen is 2:1Ratio of hydrogen to oxygen is 2:1 (just like water)(just like water)
Example: CExample: C66HH1212OO66
Basic Unit is called a saccharideBasic Unit is called a saccharide
Types of CarbohydratesTypes of Carbohydrates
MonosaccharidesMonosaccharidesSimple, single (mono-) sugar unitSimple, single (mono-) sugar unitBuilding block of all other Building block of all other
carbohydrates carbohydrates Name usually ends in –oseName usually ends in –oseUsed as energy sourceUsed as energy source
Examples of MonosaccharidesExamples of Monosaccharides Glucose – blood sugarGlucose – blood sugar Fructose – fruit sugarFructose – fruit sugar Galactose – one monomer in lactose (milk)Galactose – one monomer in lactose (milk)
Isomers of CIsomers of C6HH12OO6
Examples of MonosaccharidesExamples of Monosaccharides
Ribose and Deoxyribose Ribose and Deoxyribose 5 - Carbon sugars in RNA and DNA5 - Carbon sugars in RNA and DNA
Types of CarbohydratesTypes of CarbohydratesDisaccharidesDisaccharides
Double sugar units Double sugar units synthesized from synthesized from monosaccharidesmonosaccharides
All are isomers of All are isomers of CC12HH22OO11
Formed by Formed by dehydration dehydration synthesis (requires synthesis (requires enzymes)enzymes)
OH
OH
H
OH
H
OHH
OH
H
OH
H
HOH
OH
H
OH
H
OHH
OH
H
OH
H
H
OH
OH
H
O
H
OHH
OH
H
OH
H
HOH H
OH
H
OHH
OH
H
OH
H
H
H
O
H
Examples of DisaccharidesExamples of Disaccharides
Sucrose – table sugarSucrose – table sugar Glucose + FructoseGlucose + Fructose
Maltose – seed sugar Maltose – seed sugar Glucose + GlucoseGlucose + Glucose
Lactose – milk sugarLactose – milk sugar Glucose + GalactoseGlucose + Galactose
Types of CarbohydratesTypes of Carbohydrates
PolysaccharidesPolysaccharidesLarge, complex chains of many (poly-) Large, complex chains of many (poly-)
repeating sugar unitsrepeating sugar unitsPolymersPolymersBonded together by dehydration synthesisBonded together by dehydration synthesisUsed by living things as a sugar storage or for Used by living things as a sugar storage or for
structuresstructures
Examples of PolysaccharidesExamples of Polysaccharides Amylose – plant starch Amylose – plant starch
Used as sugar storage in seeds, roots, stemsUsed as sugar storage in seeds, roots, stems Glycogen – animal starchGlycogen – animal starch
Used as sugar storage by humans in the liverUsed as sugar storage by humans in the liver CelluloseCellulose
Very tough polymer Very tough polymer Used as a main component of cell wallsUsed as a main component of cell walls Indigestible by humansIndigestible by humans
ChitinChitin Very tough polymerVery tough polymer Used in exoskeletons (crab shells, insects)Used in exoskeletons (crab shells, insects)
Digesting PolysaccharidesDigesting Polysaccharides
Broken apart by Broken apart by hydrolysis with the hydrolysis with the help of enzymeshelp of enzymes
OH
OH
H
O
H
OHH
OH
H
OH
H
HOH H
OH
H
OHH
OH
H
OH
H
H
OH
OH
H
OH
H
OHH
OH
H
OH
H
H
OH
OH
H
OH
H
OHH
OH
H
OH
H
H
H
O
H
LipidsLipids
What are Lipids?What are Lipids? Three elements: Carbon Hydrogen OxygenThree elements: Carbon Hydrogen Oxygen Ratio of H:O much greater than 2:1Ratio of H:O much greater than 2:1
Example: Oleic acid CExample: Oleic acid C18HH34OO3
Insoluble in waterInsoluble in water Greasy, slippery textureGreasy, slippery texture Three main groups:Three main groups:
Fats oils and waxesFats oils and waxes At room temperature: Liquid – oils/Solid – fats and waxesAt room temperature: Liquid – oils/Solid – fats and waxes
PhospholipidsPhospholipids SteroidsSteroids
What are the Functions of Lipids?What are the Functions of Lipids?
Fats, Oils and Waxes:Fats, Oils and Waxes:
Long term energy storageLong term energy storage More than twice as much energy stored than More than twice as much energy stored than
carbohydrates carbohydrates fats- 9 Calories/gram; carbohydrates- 4 Cal/gfats- 9 Calories/gram; carbohydrates- 4 Cal/g
In plants: stored in and around seeds In plants: stored in and around seeds Peanut oil, corn oil, olive oilPeanut oil, corn oil, olive oil
In animals: stored under the skin and around In animals: stored under the skin and around internal organsinternal organs Used as insulation and shock absorberUsed as insulation and shock absorber
What are the Functions of Lipids?What are the Functions of Lipids?
Phospholipids Phospholipids Structural Part of Cell membranesStructural Part of Cell membranes
SteroidsSteroidsPart of cell membranes, transport of lipids, Part of cell membranes, transport of lipids,
regulate body functions (hormones) regulate body functions (hormones)
Chemical Composition Chemical Composition Fats Oils, Waxes Fats Oils, Waxes
One or more fatty acids One or more fatty acids attached to a Glycerol attached to a Glycerol backbone backbone Fatty Acids: Long chains Fatty Acids: Long chains
of carbon with a carboxyl of carbon with a carboxyl group at the endgroup at the end
Glycerol: CGlycerol: C3HH8OO3
Formed by dehydration Formed by dehydration synthesissynthesis
NOT a polymerNOT a polymer
GlycerolFatty Acid
Lipid
Glycerol
Formation of a Triglyceride:Formation of a Triglyceride:
Types of FatsTypes of Fats SaturatedSaturated
All carbons of the fatty acid have single bondsAll carbons of the fatty acid have single bonds All carbons are “filled” with hydrogenAll carbons are “filled” with hydrogen Solid at room temperatureSolid at room temperature Associated with heart disease riskAssociated with heart disease risk Examples: Bacon grease, butterExamples: Bacon grease, butter
Types of FatsTypes of Fats UnsaturatedUnsaturated
Carbons share one or more double or triple bonds Carbons share one or more double or triple bonds with other carbonswith other carbons
Monounsaturated – only one double bondMonounsaturated – only one double bond Polyunsaturated – many double or triple bondsPolyunsaturated – many double or triple bonds
Liquid at room temperatureLiquid at room temperature Examples: corn oil, olive oilExamples: corn oil, olive oil
PhospholipidsPhospholipids Phosphate Phosphate
group replaces group replaces fatty acid on fatty acid on one endone end
Used as the Used as the main main component of component of cellular cellular membranesmembranes
Steroids: Four Fused RingsSteroids: Four Fused Rings
lipids with four fused hydrocarbon rings
Includes: Cholesterol - found in animal
cell membranes Testosterone, estrogen,
progesterone - sex hormones Vitamin D
An anabolic steroid is a synthetic testosterone.
ProteinsProteins
Protein FunctionsProtein Functions
Structural partsStructural parts cell membrane, muscles, hair, nails, pigmentscell membrane, muscles, hair, nails, pigments
RegulatorsRegulators Hormones, enzymesHormones, enzymes
CarriersCarriersTransport materials in, out and around cellsTransport materials in, out and around cells
IdentificationIdentification Allow cells to recognize each other Allow cells to recognize each other Immune system antibodiesImmune system antibodies
Composition of ProteinsComposition of Proteins
Elements: Elements: carbon, hydrogen, oxygen and NITROGENcarbon, hydrogen, oxygen and NITROGEN
Very large, complexVery large, complexHemoglobin: CHemoglobin: C30323032HH48164816OO872872NN780780SS88FeFe44
Monomers (building blocks) are amino Monomers (building blocks) are amino acidsacids20 common amino acids20 common amino acids
9 are essential 11 are non essential9 are essential 11 are non essential
Amino AcidsAmino Acids
The R group is different for
each of the twenty amino
acids
Peptide BondsPeptide Bonds•Chains of amino acids are called peptides
•Amino acids are joined by dehydration synthesis
•This occurs between the carboxyl end of one amino acid and the amino end of another amino acid.
•The resulting bond is called a Peptide bond
Primary StructurePrimary Structure
The sequence of The sequence of amino acids in a amino acids in a protein is called the protein is called the Primary StructurePrimary Structure
The sequence is The sequence is unique for each unique for each protein and is protein and is determined by the determined by the DNADNA
Secondary StructureSecondary Structure
Hydrogen bonds are Hydrogen bonds are formed between the formed between the chains of amino acids chains of amino acids causing different causing different shapes.shapes.
Secondary StructureSecondary StructureTwo shapes are common – Two shapes are common –
a helix and a sheet. a helix and a sheet.
Sheet and Helix
Tertiary StructureTertiary Structure The 3-D The 3-D
arrangement of the arrangement of the molecule caused molecule caused by weak bonds by weak bonds between the R between the R groupsgroups
The most important The most important structure format structure format
Determines the Determines the function of the function of the proteinprotein
Quaternary StructureQuaternary Structure More than one protein More than one protein
molecule can molecule can combine to create a combine to create a macromoleculemacromolecule
This is the quaternary This is the quaternary structure of the structure of the proteinprotein
This creates either This creates either globular (hemoglobin) globular (hemoglobin) or fibrous (collagen) or fibrous (collagen) proteinsproteins
Nucleic AcidsNucleic Acids
Nucleic Acids are:Nucleic Acids are:The largest molecules in living thingsThe largest molecules in living thingsThe DNA of humans has about 6 billion The DNA of humans has about 6 billion
monomersmonomersSome reptiles have 20 times more unitsSome reptiles have 20 times more unitsThe largest DNA known is a flower with 5 The largest DNA known is a flower with 5
trillion unitstrillion units
The two most important The two most important Nucleic Acids:Nucleic Acids:
DNA (deoxyribonucleic DNA (deoxyribonucleic acid)acid)
RNA (ribonucleic acid)RNA (ribonucleic acid)
Functions of Nucleic AcidsFunctions of Nucleic AcidsDNADNA
make up chromosomes and their genes that make up chromosomes and their genes that carry hereditary information carry hereditary information
found in the nucleus, mitochondria and found in the nucleus, mitochondria and chloroplasts (plants)chloroplasts (plants)
RNARNA functions in the synthesis of proteins for the cellfunctions in the synthesis of proteins for the cell found in cell parts: nucleoli, ribosomes, and found in cell parts: nucleoli, ribosomes, and
throughout the cytoplasm throughout the cytoplasm
General Structure of General Structure of Nucleic AcidsNucleic Acids
Polymers, with many repeating units Polymers, with many repeating units called nucleotidescalled nucleotides
Nucleotides have three subunits:Nucleotides have three subunits:a five carbon sugara five carbon sugara phosphate groupa phosphate groupa nitrogenous basea nitrogenous base
(a base that contains nitrogen)(a base that contains nitrogen)
Phosphate group
Five Carbon Sugar
Nitrogenous Base
Structure of DNAStructure of DNA
The sugar backbone is deoxyriboseThe sugar backbone is deoxyribose
Structure of DNAStructure of DNA
The base can be one of four: The base can be one of four: AdenineAdenine GuanineGuanine ThymineThymine CytosineCytosine
Structure of DNAStructure of DNA
The bases pair upThe bases pair up – –
A (adenine) always pairs with T A (adenine) always pairs with T (thymine)(thymine)
G (guanine) always pairs with C G (guanine) always pairs with C (cytosine)(cytosine)
Structure of DNAStructure of DNA
Structure of DNAStructure of DNA
Two polymer Two polymer chains of chains of nucleotides are nucleotides are connected by connected by weak hydrogen weak hydrogen bonds and are bonds and are twisted into a twisted into a double helixdouble helix
Structure of DNAStructure of DNA
Sequence of nitrogenous bases Sequence of nitrogenous bases codes for specific amino acids codes for specific amino acids
Amino acid sequence Amino acid sequence determines the protein made in determines the protein made in the cell and the cellular activitythe cell and the cellular activity
Relationship Between Proteins and Relationship Between Proteins and Nucleic AcidsNucleic Acids
Structure of RNAStructure of RNA Ribose is its sugar backboneRibose is its sugar backbone
Structure of RNAStructure of RNAThe base can be one of four:The base can be one of four: AdenineAdenine GuanineGuanine CytosineCytosine UracilUracil
Thymine is replaced by UracilThymine is replaced by Uracil
Structure of RNAStructure of RNA Only a single polymer chain is Only a single polymer chain is
created in RNA, but strands of RNA created in RNA, but strands of RNA have complex, folded structures that have complex, folded structures that compliment their function.compliment their function.
EnzymesEnzymes
What are Enzymes?What are Enzymes?
Large, Complex ProteinsLarge, Complex ProteinsFunction as Organic CatalystsFunction as Organic Catalysts
Allow reactions to occur at lower Allow reactions to occur at lower temperatures ( 37° C)temperatures ( 37° C)
Used temporarilyUsed temporarilyUnchanged by the reactionUnchanged by the reactionCan be reusedCan be reusedSpecific to one reactionSpecific to one reaction
What are Enzymes?What are Enzymes?
Bind to reactants called substratesBind to reactants called substratesEnzyme names usually end in –ase and Enzyme names usually end in –ase and
can be named for their substrate:can be named for their substrate:Protease – proteinsProtease – proteinsLipase – lipidsLipase – lipidsMaltase – maltoseMaltase – maltoseATPase – ATPATPase – ATPAcetylcholinesterase - acetylcholineAcetylcholinesterase - acetylcholine
How Do Enzymes Work?How Do Enzymes Work?
Reduces energy needed to begin reaction Reduces energy needed to begin reaction (Activation energy)(Activation energy)
Ene
rgy
Time
Ene
rgy
Time
Without catalyst With catalyst
Activation Energy
How Do Enzymes Work?How Do Enzymes Work?
Lock and Key ModelLock and Key Model
Enzyme Enzyme Enzyme
Substrate
Active Site
Products
Substrate attaches to enzyme at active site
Enzyme Substrate Complex Formed
Reaction takes place and products are released
How Do Enzymes Work?How Do Enzymes Work?
Induced Fit ModelInduced Fit Model
Substrate attaches to active site
Enzyme changes shape to match substrate –
Stressed molecule may help to weaken bonds
Enzyme resumes original shape after product formed
Enzyme EnzymeEnzyme
SubstrateEnzyme substrate complex formed
Product
How Do Enzymes Work?How Do Enzymes Work?
Coenzymes sometimes neededCoenzymes sometimes neededNon proteins – minerals, vitaminsNon proteins – minerals, vitaminsSmaller moleculesSmaller moleculesPart of the enzyme structure or Part of the enzyme structure or
work along side the enzymework along side the enzyme
Enzyme and substrate do not match
Coenzyme fills in needed shape
Coenzyme
Denaturation:Denaturation:
If the shape changes, the enzyme cannot function properly
Factors Affecting EnzymesFactors Affecting Enzymes TemperatureTemperature
Enzyme activity Enzyme activity increases with increases with temperaturetemperature
Optimum temperature Optimum temperature for each enzymefor each enzyme
Higher temperatures Higher temperatures denature (change the denature (change the shape) of the enzyme’s shape) of the enzyme’s active siteactive site
Rate of reaction Rate of reaction decreases quickly after decreases quickly after optimum temperatureoptimum temperature
10 20 30 40 50
Optimum temperature
Factors Affecting EnzymesFactors Affecting Enzymes pHpH
Enzymes are pH dependentEnzymes are pH dependent Some work at low pH (acid) Some work at low pH (acid)
Some at high pH (basic)Some at high pH (basic) Surrounding solutions will Surrounding solutions will
activate or deactivate enzyme by activate or deactivate enzyme by changing the shape of the active changing the shape of the active site site
Extremely high or low pH values Extremely high or low pH values generally result in complete loss generally result in complete loss of activity for most enzymes of activity for most enzymes
pH for Optimum Activity EnzymeEnzyme pH OptimumpH Optimum
Lipase (pancreas)Lipase (pancreas) 8.08.0
Lipase (stomach)Lipase (stomach) 4.0 - 5.04.0 - 5.0
Lipase (castor oil)Lipase (castor oil) 4.74.7
PepsinPepsin 1.5 - 1.61.5 - 1.6
TrypsinTrypsin 7.8 - 8.77.8 - 8.7
UreaseUrease 7.07.0
InvertaseInvertase 4.54.5
MaltaseMaltase 6.1 - 6.86.1 - 6.8
Amylase Amylase (pancreas)(pancreas) 6.7 - 7.06.7 - 7.0
Amylase (malt)Amylase (malt) 4.6 - 5.24.6 - 5.2
CatalaseCatalase 7.07.0
Factors Affecting EnzymesFactors Affecting EnzymesConcentration:Concentration:
Increasing amount of enzyme: Increasing amount of enzyme: rate increases then levels offrate increases then levels offsubstrate levels fall and reduces efficiencysubstrate levels fall and reduces efficiency
Increasing amount of substrate: Increasing amount of substrate: rate increases then levels off rate increases then levels off enzyme is saturated and no additional reactions enzyme is saturated and no additional reactions
can occur can occur
Presence of InhibitorsPresence of InhibitorsBind to enzyme and change shape or Bind to enzyme and change shape or
compete with the substratecompete with the substrate