PHOTOSYNTHESIS

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PHOTOSYNTHESIS

• CHAPTER 9.2

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CHAPTER 9.2

• PHOTOSYNTHESIS comes from Greek work photo
  meaning light and syntithenai meaning to put
  together
• Photosynthesis puts together sugar molecules
  using water, carbon dioxide, and energy from light

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CHAPTER 9.2

• HAPPENS IN TWO PHASES
• LIGHT-DEPENDENT REACTION
• COVERTS LIGHT ENERGY INTO CHEMICAL ENERGY
• LIGHT-INDEPENDENT REACTION
• PRODUCES SIMPLE SUGARS
• GENERAL EQUATION
• 6CO2 6H2O?C6H12O6 6O2

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CHAPTER 9.2
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CHAPTER 9.2
CHLOROPLAST
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CHAPTER 9.2
MEMBRANES IN CHLOROPLAST CALLED THYLAKOIDS
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CHAPTER 9.2

• CHLOROPLAST
• STACKS OF MEMBRANE SACS CALLED THYLAKOIDS
• CONTAIN PIGMENTS ON SURFACE
• PIGMENTS ABSORB CERTAIN WAVELENGTHS OF LIGHT

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CHAPTER 9.2

• PIGMENTS
• ABSORB CERTAIN WAVELENGTHS OF LIGHT
• EXAMPLE CHLOROPHYLL
• ABSORBS MOST WAVELENGTHS EXCEPT GREEN
• REFLECTS GREEN
• THAT IS WHAT YOU SEE.

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CHAPTER 9.2

• What color is reflected? What colors are
  absorbed?

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CHAPTER 9.2

• PLANTS ABSORB ENERGY MOSTLY FROM THE VISIBLE
  SPECTRUM

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CHAPTER 9.2

• CHLOROPHYLL IS SO ABUNDANT THAT THE OTHER
  PIGMENTS ARE NOT VISIBLE SO THE PLANT IS GREEN
• THEN WHY DO LEAVES CHANGE COLOR IN THE FALL?

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CHAPTER 9.2

• PLANTS STOP MAKING CHLOROPHYLL WHEN THE
  TEMPERATURE DROPS AND THE OTHER PIGMENTS BECOME
  VISIBLE

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CHAPTER 9.2

• FIRST PHASE IN PHOTOSYNTHESIS REQUIRES LIGHT
  LIGHT DEPENDENT
• SUNS ENERGY ENERGIZES AN ELECTRON IN CHLOROPHYLL
  MOLECULE
• ELECTRON IS PASSED TO NEARBY PROTEIN MOLECULES IN
  THE THYLAKOID MEMBRANE OF THE CHLOROPLAST

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CHAPTER 9.2
SUNS ENERGY
CHLOROPHYLL MOLECULE
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CHAPTER 9.2

• ELECTRON FROM CHLOROPHYLL IS PASSED FROM PROTEIN
  TO PROTEIN ALONG AN ELECTRON TRANSPORT CHAIN
• ELECTRONS LOSE ENERGY
• FINALLY BONDED WITH ELECTRON CARRIER CALLED NADP
  TO FORM NADPH OR ATP
• ENERGY IS STORED FOR LATER USE

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CHAPTER 9.2

• ATP NADPH are used later in the light dependent
  reactions
• Electrons from the splitting of water supply the
  chlorophyll molecules with the electrons they
  need
• The left over oxygen is given off as a gas

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CHAPTER 9.2

• PHOTOLYSIS SPLITTING OF WATER
• HYDROGEN IONS FROM WATER ARE USED TO POWER ATP
  FORMATION WITH THE ELECTRONS
• HYDROGEN IONS ACTUALLY MOVE FROM ONE SIDE OF THE
  MEMBRANE TO THE OTHER
• CHEMIOSMOSIS COUPLING THE MOVEMENT OF HYDROGEN
  IONS TO ATP PRODUCTION

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CHAPTER 9.2

• PHOTOSYNTHESIS ANIMATION

PHOTOSYNTHESIS ANIMATION
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CHAPTER 9.2

• VOCABULARY REVIEW
• LIGHT-DEPENDENT
• PIGMENT
• CHLOROPHYLL
• ELECTRON TRANSPORT CHAIN
• ATP
• NADPH
• PHOTOLYSIS
• CHEMIOSMOSIS

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CHAPTER 9.2

• LIGHT DEPENDENT
• CONVERT LIGHT INTO CHEMICAL ENERGY

BACK TO VOCABULARY LIST
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CHAPTER 9.2

• PIGMENT
• Molecules that absorb specific wavelengths of
  light
• Chlorophyll absorbs reds and blues and reflects
  green
• Xanthophyll absorbs reds, blues, greens and
  reflects yellow

BACK TO VOCABULARY LIST
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CHAPTER 9.2

• CHLOROPHYLL
• GREEN PIGMENT IN PLANTS
• TRAPS SUNS ENERGY
• SUNLIGHT ENERGIZES ELECTRON IN CHLOROPHYLL

BACK TO VOCABULARY LIST
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CHAPTER 9.2

• ELECTRON TRANSPORT CHAIN
• SERIES OF PROTEINS EMBEDDED IN A MEMBRANE THAT
  TRANSPORTS ELECTRONS TO AN ELECTRON CARRIER

BACK TO VOCABULARY LIST
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CHAPTER 9.2

• ATP
• ADENOSINE TRIPHOSPHATE
• STORES ENERGY IN HIGH ENGERY BONDS BETWEEN
  PHOSPHATES

BACK TO VOCABULARY LIST
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CHAPTER 9.2

• NADPH
• MADE FROM NADP ELECTRONS AND HYDROGEN IONS
• MADE DURING LIGHT REACTION
• STORES HIGH ENERGY ELECTRONS FOR USE DURING LIGHT
  INDEPENDENT REACTION

BACK TO VOCABULARY LIST
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CHAPTER 9.2
BACK TO VOCABULARY LIST
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CHAPTER 9.2

• CHEMIOSMOSIS
• THE COMBINATION OF MOVING HYDROGEN IONS ACROSS A
  MEMBRANE TO MAKE ATP

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CHAPTER 9.2

• LIGHT INDEPENDENT REACTION
• ALSO CALLED THE CALVIN CYCLE
• TAKES PLACE IN THE STROMA OF THE CHLOROPLAST
• TAKES CARBON DIOXIDE AND CONVERTS INTO SUGAR

STROMA
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CHAPTER 9.2

• CYCLE BECAUSE IT ENDS WITH A CHEMICAL USED IN THE
  FIRST STEP

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CHAPTER 9.2

• BEGINS WITH RuBP AND ADDS CARBON DIOXIDE TO IT
  FIXING THE CARBON DIOXIDE IN A COMPOUND
• ONE COMPOUND MADE ALONG THE WAY IS PGAL
• PGAL CAN BE MADE INTO SUGARS OR RuBP
• USES ATP AND NADPH

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• PHOTOSYNTHESIS
• 6CO2 6H2O? C6H12O6 6O2