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AIM: SWBAT describe the 3 steps of the light independent reactions
(Calvin Cycle)Please Do Now: Answer the following two
questions:1) What role does sunlight play in the electron
transport chain?2) Where do the electrons that are passed through
the electron transport chain come from?
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AgendaDo NowData AnalysisLight Independent Cycle NotesVideo ClipFinish Light Dependent WorksheetCalvin Cycle Worksheet
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Data AnalysisYou will be a presented a series of graphs and
charts (every Thursday)For each chart or graph, on a blank sheet of
paper you will answer 1-2 questions (INDEPENDENTLY AND QUIETLY).
Once we have gone through all of them, you will be posed a question that unifies all the figures. Respond in 3-4 sentences.
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What colors are used in photosynthesis?: Chart 1
1. What percent of plants worldwide have leaves that are some color other than green?
2. What is the pigment that absorbs light for photosynthesis in plants?
Color of Leaves
Green Red Black Blue/Purple
% of plants worldwide with that color
99.78% 0.17% 0.01% 0.04%
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What colors are used in photosynthesis?: Chart 2
This graph details an experiment that tests photosynthesis. The more disks that are floating, the more photosynthesis is happening.
1. What is measured on the Y axis?
2. What is shown on the X axis?
3. Which color of light has the most photosynthesis taking place?
4. What color of light has the least photosynthesis taking place?
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What colors are used in photosynthesis?: Chart 3
1. What is shown along the x axis?
2. What colors of light have the highest % of absorption?
3. What colors of light have the lowest % of absorption?
%
(color)
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Putting it all togetherIn 2-3 sentences, tell me what colors of light
are used in photosynthesis and how you know that (cite specific graphs/charts).
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Light Reactions EVEN MORE BRIEFLY
Sunlight inChemical Energy out(ATP and NADPH)
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Photosynthesis
Chemical Energy
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What is the purpose of the Light Independent Reactions
Uses the ATP from the light reactionsTakes place is the stroma of the chloroplast
(outside the thylakoid, inside the chloroplast).3 steps: 1. carbon fixation, 2. reduction 3.
regeneration
ALSO KNOWN ASDARK REACTIONS
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Light Independent Reactions: Step 1Carbon fixation
The enzyme RuBisCo combines the 5-Carbon compound RuBP with carbon dioxide (CO2) to make an unstable 6 carbon compound
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Light Independent Reactions: Step 2Reduction: The
unstable 6 carbon compound is split apart and reduced into 2 molecules with 3 Carbons, called G3PRequires ATP and
NADPH
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Light Independent Reactions Step 3• Regeneration: A large
array of enzymes rearrange 5 G3P molecules into 3 RuBP molecules, which start off the Calvin cycle ATP required
1 G3P can be taken out of the cycle every 3 turns, to go toward making glucose
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Summary1 carbon dioxide is fixed per turn of the cycleEach turn takes 3 ATP and 2 NADPH, made
in the light reactions (lots of energy!)To make one glucose, it takes six turns of the
cycle
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Demo Time= carbon molecules (glucose has 6, RuBP 5, G3P 3, carbon dioxide 1)
= ATP or NADPH molecules
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Practice QuestionsIn the overall equation for photosynthesis, six
molecules of carbon dioxide result in six molecules of
a. glucose.b. water.c. oxygen.d. ATP.
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Practice QuestionsIn the overall equation for photosynthesis, six
molecules of carbon dioxide result in six molecules of
a. glucose.b. water.c. oxygen.d. ATP.
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a. thylakoids.
b. chloroplasts.
c. plant cells.
d. all of the above
The stroma is the space that surrounds
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a. thylakoids.
b. chloroplasts.
c. plant cells.
d. all of the above
The stroma is the space that surrounds
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If carbon dioxide is removed from a plant’s environment, what would you expect to happen to the plant’s production of high-energy sugars?
a. More sugars will be produced.
b. Fewer sugars will be produced.
c. The same number of sugars will be produced but without carbon dioxide.
d. Carbon dioxide does not affect the production of high-energy sugars in plants.
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If carbon dioxide is removed from a plant’s environment, what would you expect to happen to the plant’s production of high-energy sugars?
a. More sugars will be produced.
b. Fewer sugars will be produced.
c. The same number of sugars will be produced but without carbon dioxide.
d. Carbon dioxide does not affect the production of high-energy sugars in plants.
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What is the role of RuBP in the light independent reactions?
A. It reduces the 6-carbon molecule and forms 2 G3Ps
B. It provides the chemical energy for the regeneration step
C. It is what carbon dioxide is fixed on to in the first step of the Calvin cycle
D. It is one of the enzymes in the regeneration step
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What is the role of RuBP in the light independent reactions?
A. It reduces the 6-carbon molecule and forms 2 G3Ps
B. It provides the chemical energy for the regeneration step
C. It is what carbon dioxide is fixed on to in the first step of the Calvin cycle
D. It is one of the enzymes in the regeneration step
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It takes 3 molecules of ATP every turn of the Calvin cycle. How many molecules of ATP does it take to fix enough carbon for a 6 carbon molecule like glucose?A. 9B. 18C. 27D. 54
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It takes 3 molecules of ATP every turn of the Calvin cycle. How many molecules of ATP does it take to fix enough carbon for a 6 carbon molecule like glucose?A. 9B. 18C. 27D. 54