Photosynthesis and Respiration

Photosynthesis and Respirationan introductionLets start withPhotosynthesisThe 5 Ws of PhotosynthesisWho?The major players are:Carbon dioxide, water, glucose, oxygen, sunlight, and ATP

The 5 Ws of PhotosynthesisWhat?Photosynthesis = you tell me!2 types of reactions:Light-dependent = converting sunlight energy to chemical energy (ATP)Light-independent = uses chemical energy to produce simple sugarsThe big equation6 CO2 + 6 H2O C6H12O6 + 6 O2lightThe 5 Ws of PhotosynthesisWhen?

Light-dependent

Light-independentThe 5 Ws of PhotosynthesisWhere?Plant cells!

Key words: chloroplast, chlorophyll (pigment), thylakoid membrane, photosystemsChloroplast thylakoid membranes contain chlorophyll pigments7The 5 Ws of PhotosynthesisWhy?Lets review the 5 requirements for living things:Orderly structureReproduceAdapt to their environment*Grow and develop**Require energy*The 5 Ws of PhotosynthesisHow?Light-dependent reactions:Light = energyExcites electrons in chlorophyllMove down electron transport chain (proteins) in thylakoid membraneEach stair step down chain releases energy to:Break H2O to release oxygen and new electrons,Pump H+ in to create NADPH, andBind P to ADP, forming ATP

Photolysis Figure 9.5 (Sect 9.2)

Light-Dependent ReactionsThe 5 Ws of PhotosynthesisHow? contdLight-independent reactions:Calvin Cycle in stroma of chloroplastCO2 in & 6-carbon sugars (glucose) out

And nowRespirationThe 5 Ws of RespirationWho?The major players are:Carbon dioxide, water, glucose, oxygen, and ATPDoes this look familiar?

The Respiration EquationC6H12O6 + 6O2 6CO2 + 6H2O + Energy The 5 Ws of RespirationWhat?Cellular respiration = the break down of food molecules to produce ATP3 stages:Glycolysis = breaks down glucose to pyruvic acidCitric acid cycle (aka Krebs cycle) = similar to the Calvin cycle; produces CO2 and ATPElectron transport chain = energy released in steps to produce ATP and H2OThe 5 Ws of RespirationWhen?Glycolysis = anaerobic (anytime)Citric acid cycle and electron transport chain = aerobic (needs __________)oxygenThe 5 Ws of RespirationWhere?In all living cells!Glycolysis: in cytoplasmCitric acid cycle: in mitochondriaElectron transport chain: in inner membrane of mitochondria

Where are these places? A quick tour of the cell

Lets zoom in a little furtherThe Mitochondria

Does this structure remind you of anything we talked about earlier?

The Chloroplast!aka the Power house of the cellThe 5 Ws of RespirationWhy?2nd step in releasing energy for the organismRemember the requirements of life!The 5 Ws of RespirationHow?3 stages:Glycolysis = breaks down glucose to pyruvic acid*FermentationCitric acid cycle (aka Krebs cycle) = similar to the Calvin cycle; produces CO2 and ATPElectron transport chain = energy released in steps to produce ATP and H2O

Electron transport chainFYI

Figure 9.11The 5 Ws of RespirationHow? ContdFermentation = occurs, for example, during heavy exercise when cells are lacking oxygenOxygen is the final electron acceptor in the electron transport chain. Without it, energy (ATP) cannot be producedDefinition: Anaerobic means of creating ATP(supplies energy when oxygen is scarce)2 types:Lactic acidAlcoholic

Lactic acid fermentationForms lactic acid in musclesAlcoholic fermentationUsed by yeast cells and bacteria to produce CO2 and alcohol (i.e. bread)

Lets make some comparisons:Figure 9.12

ReviewTable 9.1

Video time!The Light ReactionsBill Nye Plant PigmentsCowboy Respiration