Chapter 14 Energy generation in Mitochondria and Chloroplasts

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Chapter 14 Energy generation in Mitochondria and
Chloroplasts
Not responsible for 1) Detailed mechanism of
the Ps reaction center (Figure 14-31) 2)
Photosynthesis in bacteria (pp 488-490)
View The Virtual Cell animations for - e-
transport - ATP synthase - photosynthesis
Questions in this chapter you should be able to
answer Chapter 14 1 - 4, 6 12, 14 -23
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A Quick review How is energy transferred to
ATP? Substrate-level phosphorylation Pi
comes from a substrate molecule Chemios
motic phosphorylation ATP synthesis is coupled
to NADH oxidation
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How is oxidation of NADH coupled to ATP synthesis?
E- transport -? H pumping -? ATP synthase
Which creates a proton-motive force through a
H electrochemical gradient
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What are the molecular components of the e-
transport system?
E- transport
Question 14-3, p 461 What are consequences of DNP
and nigericin on the proton gradient?
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Why do e-transport proteins bind e-
? Iron-sulfur groups heme groups of cytochromes
Why do electrons pass between e- transport
proteins? Iron-sulfur groups (lower redox
potential) heme groups (higher redox potential)
Cytochrome-bc1
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What is the mechanism the ATP synthase?
ATP synthase is also an ATPase
ATP synthase model
ATP synthase animation
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• What is the evidence that ATP synthesis is driven
  by Chemiosmosis?
• Effect of decouplers pH 2) Artificial systems
• -- bacteriorhodopsin
• -- ATPase

Question 14-19, pg 464
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Energy capture during photosynthesis What is the
structure of chloroplasts? What are the two
stages of Ps?
True or false The light-independent reactions
only occur in the presence of light. Explain.
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How is energy captured by chlorophyll? Antenna
(light harvesting) complex Reaction Center
Chl
Porphyrin ring
Reaction Center
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How is ATP and NADH generated during the light
reactions? Z-scheme P680 and P700 Rx
centers Coupling to chemiosmosis NADP
reduction Membrane architecture
Question 14-10 p 486 Chloroplasts do not have an
ATP transporter. How then do plant cells obtain
ATP to carry out other metabolic processes?
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What does the Z-scheme show? Why does cyclic
photophosphorylation occur?
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How is CO2 fixed into organic form? --
light-independent Rxs -- Calvin / Bensen
cycle -- RUBP carboxylase oxygenase (Rubisco)
1. CO2 Fixation RUBP carboxylase-oxygenase
(Rubisco) 2. Carbon Reduction 3. RUBP
regeneration