A fond tribute to Photosynthesis and Chapter 10
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Overview: The Process That Feeds the Biosphere
Photosynthesis
–Is the process that converts _________ energy into _________ energy
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Plants and other ______trophs
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Plants are ____________trophs
–Are the ___________ of the biosphere
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They use the energy of sunlight to make organic molecules from ______ and ______
________
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Photosynthesis: Occurs in plants, ______, certain other _________, and some
________
–_______trophs
–Obtain their organic material from _____organisms
–Are the ____________ of the biosphere
–The leaves of plants
–Are the major sites of photosynthesis
–Chloroplasts
–Are the organelles in which photosynthesis occurs
–Contain _________ and _________
–Photosynthesis is summarized as
–WRITE THE EQUATION BELOW:
WHAT GOES IN? WHAT COMES OUT?
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Chloroplasts split _______ into
–Hydrogen and oxygen, incorporating the electrons of hydrogen into sugar molecules
–_______ reactions
–Transfer electrons from one reactant to another by oxidation and reduction
–In oxidation
–A substance _______ electrons, or is oxidized
–In reduction
–A substance ________ electrons, or is reduced
–Examples of redox reactions (Write below)
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–Some redox reactions
–Do not completely exchange electrons
–Change the degree of electron sharing in covalent bonds
–Photosynthesis is a redox process
–Water is _______, carbon dioxide is ________
–Photosynthesis consists of two processes
–The _______ reactions
–The _______ cycle
Circle both processes with a different colored pen
–The light reactions
–Occur in the __________
–Split _____, release _____, produce ____, and form ________
–The Calvin cycle
–Occurs in the ________
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Forms ______ from carbon dioxide, using ATP for energy and NADPH for reducing
power
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An overview of photosynthesis (Where is this occurring? What cell components are
major players?
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Concept 10.2: The light reactions convert solar energy to the chemical energy of
______ and _________
–Light
–Is a form of electromagnetic ________, which travels in waves
–Wavelength
–Is the distance between the crests of waves
–Determines the type of electromagnetic energy
–The electromagnetic spectrum
–Is the entire range of electromagnetic energy, or radiation
–The visible light spectrum
–Includes the _______ of light we can see
–Includes the wavelengths that drive ___________
–Pigments
–Are substances that _________ visible light
–_______ light, which include the colors we see
–The spectro________meter
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Is a machine that sends light through pigments and measures the fraction of light
__________ at each wavelength
–An absorption spectrum
–Is a graph plotting light absorption versus wavelength
–The absorption spectra of chloroplast pigments
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Provide clues to the relative effectiveness of different wavelengths for driving
photosynthesis
–The absorption spectra of three types of pigments in chloroplasts
–Chlorophyll a
–Is the main photosynthetic pigment
–Chlorophyll b
–Is an accessory pigment
–Other accessory pigments
–Absorb _______ wavelengths of light and pass the _______ to chlorophyll a
–When a pigment absorbs light
–It goes from a _______ state to an _________state, which is unstable
–A ___________: A Reaction Center Associated with Light-Harvesting Complexes
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Is composed of a reaction center surrounded by a number of light-harvesting
complexes
–The light-harvesting complexes
–Consist of _________ molecules bound to particular ________
–Funnel the _________ of photons of light to the reaction center
–When a reaction-center chlorophyll molecule absorbs energy
–One of its electrons gets bumped up to a primary electron _____________
–The ___________ membrane
–Is populated by two types of ____________, I and II
–___________ electron flow
–Is the primary pathway of energy transformation in the light reactions
–Produces __________, ______, and ______
–A mechanical analogy for the light reactions
–Under certain conditions
–Photoexcited electrons take an alternative path
–In _______ electron flow
–Only photosystem ___ is used
–Only _____ is produced
–Chloroplasts and mitochondria
–Generate ATP by the same basic mechanism: chemiosmosis
–But use different sources of energy to accomplish this
–The spatial organization of chemiosmosis
–Differs in chloroplasts and mitochondria
–In both organelles
–Redox reactions of electron transport chains generate a _________ across a membrane
–ATP ________
–Uses this proton-motive force to make ATP
–The light reactions and chemiosmosis: the organization of the thylakoid membrane
–Concept 10.3: The Calvin cycle uses _____ and ______ to convert ____ to _______
–The Calvin cycle
–Is similar to the citric acid cycle
–Occurs in the ________
–The Calvin cycle has three phases
–_______ fixation
–_________
–Regeneration of the _____ acceptor
–The Calvin cycle
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Concept 10.4: Alternative mechanisms of ______ fixation have evolved in ____,
_____climates
–On hot, dry days, plants ____ their _______
–Conserving water but limiting access to ______
–Causing _______ to build up
–In ______respiration
–O substitutes for CO in the active site of the enzyme rubisco
–The photosynthetic rate is reduced
–____ plants minimize the cost of photorespiration
–By incorporating _____ into ____ carbon compounds in mesophyll cells
–These four carbon compounds
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Are exported to _______ ______ cells, where they release _______ used in the Calvin
cycle
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–C leaf anatomy and the C pathway
–_______ plants
–Open their ______ at night, incorporating CO into organic ______
–During the day, the stomata _____
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–And the ______ is released from the organic acids for use in the Calvin cycle
–The CAM pathway is similar to the C pathway
–A review of photosynthesis
–Organic compounds produced by photosynthesis
–Provide the energy and building material for ecosystems
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