28
Figure 7.UN01
becomes oxidized(loses electron)
becomes reduced(gains electron)
Figure 7.UN03
becomes oxidized
becomes reduced
Figure 7.5
Explosiverelease
(a) Uncontrolled reaction (b) Cellular respiration
H2O
Fre
e en
erg
y, G
Fre
e en
erg
y, G
Electro
n tran
spo
rt
chain
Controlledrelease of
energy
H2O
2 H
2 e−
2 H 2 e−
ATP
ATP
ATP
½
½
½H2 O2 O2
O2
2 H
Figure 7.UN05
Glycolysis (color-coded teal throughout the chapter)
Pyruvate oxidation and the Krebs (citric acid)cycle(color-coded salmon)
1.
Oxidative phosphorylation: electron transport andchemiosmosis (color-coded violet)
2.
3.
Figure 7.6-1
Electronsvia NADH
Glycolysis
Glucose Pyruvate
CYTOSOL
ATP
Substrate-level
MITOCHONDRION
Figure 7.6-2
Electronsvia NADH
Glycolysis
Glucose Pyruvate
Pyruvateoxidation
Acetyl CoA
Krebscycle
Electronsvia NADH and
FADH2
CYTOSOL
ATP
Substrate-level
ATP
Substrate-level
MITOCHONDRION
Figure 7.6-3
Electronsvia NADH
Glycolysis
Glucose Pyruvate
Pyruvateoxidation
Acetyl CoA
Krebscycle
Electronsvia NADH and
FADH2
Oxidativephosphorylation:electron transport
andchemiosmosis
CYTOSOL
ATP
Substrate-level
ATP
Substrate-level
MITOCHONDRION
ATP
Oxidative
Intermembrane space
Matrix
Inner membraneOuter membrane
5 Cristae
Figure 7.UN06
Glycolysis Pyruvateoxidation
Krebscycle
Oxidativephosphorylation
ATP ATP ATP
Figure 7.8
Energy Investment Phase
Energy Payoff Phase
Net
Glucose
Glucose
2 ADP 2 P
4 ADP 4 P
2 NAD 4 e− 4 H
2 NAD 4 e− 4 H
4 ATP formed − 2 ATP used
2 ATP
4 ATP
used
formed
2 NADH 2 H
2 Pyruvate 2 H2O
2 Pyruvate 2 H2O
2 NADH 2 H
2 ATP
Figure 7.UN07
Glycolysis Pyruvateoxidation
Krebscycle
Oxidativephosphorylation
ATP ATP ATP
Figure 7.10a
CYTOSOLPyruvate(from glycolysis,2 molecules per glucose)
CO2
CoANAD
NADH
MITOCHONDRION CoAAcetyl CoA H
Figure 7.10b
CoA
Krebscycle
FADH2
FAD
ADP Pi
ATP
NADH
3 NAD
3
3 H
2 CO2
CoAAcetyl CoA
Figure 7.11-6
NADH
NAD
H
8
Malate
Succinate
FAD
FADH2
Fumarate
H2O7
6
Acetyl CoA
Oxaloacetate
Citrate
H2O
Isocitrate
NADH
NAD
H
CO2
-Ketoglutarate
Krebscycle
CoA-SH
CO2NAD
NADH
H
ATP formation
SuccinylCoA
ADP
GDPGTP
Pi
ATP
5
4
1
CoA-SH
3
CoA-SH
2
Figure 7.UN09
Glycolysis Pyruvateoxidation
Krebscycle
Oxidativephosphorylation:electron transportand chemiosmosis
ATP ATP ATP
Figure 7.14
Proteincomplexof electron carriers
H
HH
H
Q
I
II
III
FADH2 FAD
NADNADH
(carrying electronsfrom food)
Electron transport chain
Oxidative phosphorylation
Chemiosmosis
ATPsynthase
H
ADP ATPPi
H2O2 H ½ O2
IV
Cyt c
1 2
Figure 7.15
Electron shuttlesspan membrane
CYTOSOL2 NADH
2 NADH
2 FADH2
or
2 NADH
Glycolysis
Glucose 2Pyruvate
Pyruvateoxidation
2 Acetyl CoA
Krebscycle
6 NADH 2 FADH2
Oxidativephosphorylation:electron transport
andchemiosmosis
about 26 or 28 ATP 2 ATP 2 ATP
About30 or 32 ATPMaximum per glucose:
MITOCHONDRION
Figure 7.UN11
Inputs
GlucoseGlycolysis
2 Pyruvate 2
Outputs
ATP NADH 2
Figure 7.UN12
Inputs
2 Pyruvate 2 Acetyl CoA
2 OxaloacetateKrebscycle
Outputs
ATP
CO2
2
6 2
8 NADH
FADH2
Bell Work: Draw a flow diagram depicted how reactants and products flow through the 3 steps of cellular respiration
Alcoholic Fermentation• Pyruvate releases CO2
• Resulting compound reduced by NADH to ethanol
• Bacteria
• Pyruvate reduced by NADH to lactate
• Animals, fungi, and bacteria
• Buildup causes muscle fatigue (ATP use outpaces O2 supply)
Lactic Acid Fermentation
Animation: Fermentation OverviewRight click slide / Select play
In respect to evolution, why is glycolysis so important?
Ancient prokaryotes are thought to have used glycolysis long before there was oxygen in the atmosphere
Very little O2 was available in the atmosphere until about 2.7 billion years ago, but bacteria have been dated back 3.5 billion years
Early prokaryotes likely used only glycolysis to generate ATP
Glycolysis is a very ancient process
