2 8-1 Energy of LifeEnergy=Living organisms depend on energy.Living things get energy from _______.The ultimate source of energy is the _____.The ability to do workfoodsun
3 Autotrophs and Heterotrophs Example: plants use sunlight to make foodHeterotrophs=Example: ___________- eat plants___________- eat animals thathave stored energy fromplants they eat___________- eat decomposingorganismsOrganisms that make their own foodOrganisms that need to consumefood for energyherbivorescarnivoresdetritovores
4 B. Chemical Energy and ATP Forms of energy: light, heat, electricity, and_____ (Adenosine Triphosphate)=Section 8-1Chemical energy (stored in bonds)ATPThe basic energy source (chemical energy) of all cellsAdenineRibose3 Phosphate groups
5 Storing EnergyADP (Adenosine Diphospate) contains ____ phosphates instead of 3.If a cell has extra energy,2. Releasing EnergyTo release energy stored in ATP,2Small amounts can be stored by adding aphosphate group to ADP molecules to produce ATP.The cell can break the high energy bond betweenthe 2nd and 3rd phosphate group
6 Figure 8-3 Comparison of ADP and ATP to a Battery Section 8-1ADPATPEnergyEnergyAdenosine diphosphate (ADP) + PhosphateAdenosine triphosphate (ATP)PartiallychargedbatteryFullychargedbattery
7 Using Biochemical Energy How ATP is used in the cell-- aids inCells contain a small amount of ATP.Only enough to provide a few seconds of activity.ATP is great at ________________ but not good atGlucose stores ___ times more energy than ATP.The energy stored in Glucose can be used toCarry out active transportmoving organelles throughout the cellProtein synthesisProducing light (ex. fireflys)transferring energyStoring large amounts of energy90regenerate ATP when the cell needs it.
8 8-2 Photosynthesis: An Overview Plants convert ______________ into ______________through a series of oxidation/reduction reactions.Process where plants use energy of sunlightto convert water and carbon dioxide intohigh-energy Carbohydrates-sugars-starches-and oxygen, a waste product.Sunlight energyChemical energy6 CO2 + 6H2O + SUNLIGHT → C6H12O6 (SUGAR) + 6O2
11 Light Energy Chloroplast (Chlorophyll) Sugars + O2 CO2 + H2O Photosynthesis: Reactants and ProductsSection 8-2Light EnergyChloroplast(Chlorophyll)Sugars + O2CO2 + H2O
12 A. Investigating Photosynthesis Investigations into photosynthesis began with thefollowing question:“When a tiny seedling grows intoa tall tree with a mass of several tons,where does the tree’s increase in mass come from?”
13 ______________ Experiment (1643) Put soil in pot and took massTook a seedling and took massPut seed in soil...watered...waited five years...the seedling became a tree.He concluded thatHe determined theVan Helmont’sthe mass came from water“hydrate” in the carbohydrateportion of photosynthesis
14 Von Helmont Willow Tree Experiment http://www. teachersdomain 5 years2.3 kg. (5 lb.) plant90.8 kg (200 lbs). soil76.8 kg (169 lbs. 3 oz.) Soil 57 g less
15 ___________ Experiment (1771) Put a lit candle in a bell jar-Placed a mint plant in the jar with the candle-ConcludedHe determinedPriestly’sThe flame died out.Flame lasted longerplants release a substance neededfor candle burning.plants release oxygen
16 Alternate Priestly Experiment Credit: The National Science Teachers Association
17 ________________Experiment (1779) Put aquatic plants in light...Put aquatic plants in dark...He determined:_______________ (1948)He determinesKnown as theJan Ingenhouszproduced oxygenNo oxygenLight is needed to produce oxygenMelvin Calvincarbon’s path to make glucoseCalvin’s cycle
19 B. Light and PigmentsPhotosynthesis requires ______ (soil), ____________ (air),and ____ (sun), and ________ (a molecule in chloroplasts).Energy from the sun is in the form of _____.Sunlight= perceived as white light=The wavelengths you can see are part of the_______________.Plants capture light with light absorbing molecules called________.The main pigment is chlorophyll (2 kinds)waterCarbon dioxidelightchlorophylllightA mixture of differentwavelengthsVisible SpectrumpigmentsChlorophyll aChlorophyll b
20 Chlorophyll absorbs light in the __________ and ___ wavelengths Blue-violetFigure 8-5 Chlorophyll Light AbsorptionredSection 8-2Absorption of Light byChlorophyll a and Chlorophyll bREDORANGEYELLOWGREENBLUEINDIGOVIOLETChlorophyll bChlorophyll aGamma raysX-raysUVInfraredMicro- wavesRadiowavesVisible lightWavelength (nm)VBGYOR
21 Chlorophyll reflects ______ wavelengths (that’s why plants appear green)The energy absorbed by chlorophyll is transferred to_________ (in chloroplasts) which makesphotosynthesis work.greenelectronsQUESTION: So why do plants leaves change color in the fall?Colorful leaves signal the changes of autumn. As nights grow longer and cooler, the leaves no longer produce chlorophyll, the pigment that makes leaves green and enables the process of photosynthesis. As the green pigment wanes, other pigments take over, producing the brilliant reds, oranges, and yellows of fall foliage.
22 The location and structure of chloroplasts LEAF CROSS SECTIONMESOPHYLL CELLLEAFMesophyllCHLOROPLASTIntermembrane spaceOutermembraneGranumInner membraneGranaStromaThylakoid compartmentStromaFigure 7.2Thylakoid
23 8-3 The Reactions of Photosynthesis A. Inside a ChloroplastSite of Photosynthesis=The chloroplastsReflected lightLightChloroplastAbsorbed lightTransmitted light
24 Photosynthesis is a two part process: -aka: 2. Light-dependent reactions (located in thylakoid membranes)Light ReactionLight-independent reactions (located in stroma)Dark reactionFigure 8-7 Photosynthesis: An OverviewCalvin CycleSection 8-3Carbon fixationH20LightO2SugarsCO2ChloroplastChloroplastNADP+ADP + PLight-DependentReactionsCalvinCycleATPNADPH
25 LIGHT REACTIONS (in grana) CALVIN CYCLE (in stroma) An overview of photosynthesisH2OCO2ChloroplastLightNADP+ADP +PLIGHT REACTIONS (in grana)CALVIN CYCLE (in stroma)ATPElectronsNADPHO2SugarFigure 7.5
26 2e- B. Electron Carriers Sunlight energy is transferred to The electronsHigh energy electrons requireANALOGY: If you wanted to transfer hot coals from one campfire to another, it requires a special carrier like a pan or bucket.Electron carriers pass electrons from carrier to carrierto carrier;A Key electron carrier in photosynthesis is NADP+.NADP →→(electron carrier) (high energy electrons) (hydrogen ions) (energy storing compound)When energy is needed to do cellular work, theelectrons in chlorophyll.gain a lot of energy.a special carrier(molecule/compound).Forming an electron transport chain.2e-H+NADPHCovalent bonds of NADPH are broken to releasethe high energy electrons.
27 Light-Dependent Reactions (Requires Light) Light-Dependent Reactions (Requires Light) · Located in the ___________________________ · In the light reaction, ___________ is used to produce _____ and _______thylakoid membranelight energyATPNADPH
28 Overview of the Light Reaction Electron Transport ChainElectron Transport Chaine~e~e~ADP ATPe~NADP NADPHlightlightPSIIPSI2H2OO2 + 4H+4e~
29 Primary electron acceptor Electron transport chainElectron transportPhotonsPHOTOSYSTEM IPHOTOSYSTEM IIEnergy for synthesis ofby chemiosmosis
30 KEY PLAYERS IN LIGHT REACTION: · Photosystem I and II:· Electron carriers:· Water:ATP Synthase:Clusters of chlorophyll pigmentADP and NADP+Donates electronsEnzyme (protein) that makes ATP
31 Primary electron acceptor PHOTOSYSTEMPhotonReaction centerPigment molecules of antennaFigure 7.7C
33 ELECTRON TRANSPORT CHAIN The production of ATP by chemiosmosis in photosynthesisThylakoid compartment (high H+)LightLightThylakoid membraneAntenna moleculesStroma (low H+)ELECTRON TRANSPORT CHAINPHOTOSYSTEM IIPHOTOSYSTEM IATP SYNTHASEFigure 7.9
34 A. Photosystem II (PSII). Absorbs light to. 2H2O. o e- =. o O2 = A. Photosystem II (PSII) * Absorbs light to 2H2O o e- = o O2 = o H+= B. Electron Transport Chain * The light energy * The electrons get passedsplit (break up) water molecules→ 4H e- + O2Donated to chlorophyllReleased into air providing oxygen for usReleased inside the thylakoid membraneexcites electrons increasingtheir energy level.down an electron transport chain tophotosystem I (PSI)
35 C. Photosystem I. · Light energy energizes electrons C. Photosystem I · Light energy energizes electrons. · NADP+ accepts the electrons and an H+ and are used to make _________. D. Hydrogen Ion Movement · When water splits, · The difference in charges E. ATP Formation · _____ do not cross the membrane directly It needs the help of a membrane protein. · H+ ions pass through the protein:NADPHH+ ions fill up the inner thylakoid membrane(making it positively charged). As a result, thestroma is negatively charged.Provides the energy to make ATP.IonsATP synthase is an enzyme that converts ADP to ATP
36 PRODUCTS OF THE LIGHT REACTION: · ____ : Released in the air · ______________: These contain abundant chemical energy but they are unstable. So, they are used to power the dark reaction to _________________ which can store the energy for longer periods of time.O2ATP & NADPHhelp build glucose
37 Stroma with or without light. Section 8-3 D. The Calvin Cycle (dark reaction; light independent) * Occurs in theFigure 8-11 Calvin CycleStroma with or without light.CO2 Enters the CycleEnergy InputChloropIast5-CarbonMoleculesRegenerated6-Carbon SugarProducedSugars and other compounds
38 Section 9.2 Summary – pages 225-230 (CO2)The Calvin Cycle(CO2)(Unstable intermediate)(RuPB)ADP +ATPATPADP +NADPHNADP+(PGAL)(PGAL)(PGAL)(Sugars and other carbohydrates)Section 9.2 Summary – pages
39 DARK REACTION PROCESS: A. CO2 enters the system product=B. Energy inputThe _________________________________ are used toC. 6-Carbon Sugar is produced___ of the 12 3-C are used to make glucose andother compounds.D. 5-Carbon Molecules Regenerated___ remaining 3-C are converted into 6 5-C molecules6 CO2 combines with 6 5-C compounds12 3-C compoundsATP & NADPH (from the light reaction)convert the 12 3-C compounds into a higher energy form.210
40 PRODUCTS OF THE CALVIN CYCLE (DARK REACTION):. E PRODUCTS OF THE CALVIN CYCLE (DARK REACTION): * E. Factors Affecting Photosynthesis * * Plants often have a ______ coating to protect against * * The greater the _____________, the better photosynthesis functions (up to a point).High Energy SugarsShortage of water can stop/slow down photosynthesiswaxyVery low/high temperatures (damages enzymes) canstop/slow down photosynthesis (optimal temp.= 0°– 35° CLight intensity
41 Concept Map Photosynthesis Light- dependent reactions Calvin cycle Section 8-3PhotosynthesisincludesLight-dependentreactionsCalvin cycletakes place inusesusetake place inThylakoidmembranesStromaNADPHATPEnergy fromsunlightto produceofto produceATPNADPHO2ChloroplastsHigh-energysugars
42 California State Standards Cell Biology1a: usable energy is captured from sunlight by chloroplasts and is stored through the synthesis of sugar from carbon dioxide
43 Warm up 8-1Draw an ATP molecule and describe why it is considered an energy molecule.Why do animals have to eat to gain energy and plants do not?Why do organisms need energy?
44 Warm-up 8-2 Describe what the data represents in figure 8-5 pg 207. Why are plants green?What do plants need to grow? Where are they obtaining these substances?
45 Warm-up 8-3Diagram the process of photosynthesis in detail.
46 United Streaming video: Photosynthesis (13 min)