Download Cellular Respiration

Objective: You will be able to compare and
contrast the equations of respiration.
Do Now:
• Read p. 221
• What is the most important use of food?
ATP
 Contain three phosphate groups
 Have energy between phosphate bonds
 ATP supplies energy by breaking the
bonds between phosphates
 Energy is used to carry out chemical
reactions
 The bonds are restored by respiration
Figure 6.10 The ATP cycle
The Structure of ATP
• ATP (adenosine triphosphate)
– Is the cell’s energy
– Provides energy for cellular functions
Adenine
N
O
O
-O
O
-
O
-
Phosphate groups
Figure 8.8
O
O
C
C
N
HC
O
O
O
NH2
N
CH2
-
O
H
N
H
H
H
OH
CH
C
OH
Ribose
Respiration Equation
C6H12O6 + 6O2
6CO2 + 6H2O + 36ATP
Breaking down glucose with oxygen allows us
to make 38 ATP
Anaerobic respiration
• Occurs without oxygen
• Only makes 2 ATP
• Also called fermentation
Anaerobic respiration in humans
• When we can’t get enough oxygen to our
muscles, they become fatigued.
• We then have to do respiration without
using oxygen
C6H12O6
Lactic acid + 2ATP
Anaerobic respiration in yeast
• Produces alcohol and CO2
C6H12O6
Alcohol + CO2 +2 ATP
Global Warming
• Is partly caused by an increase of CO2 in
the air?
• Why would cutting down a forest and
leaving the trees to rot increase the effect
of global warming?
Create your own lab day!
Bromthymol
• Used to test for the presence of carbon
dioxide (CO2)
• If CO2 is present it is a yellow color
• If CO2 is NOT present it is a blue color
How does exercise affect the
disposal of CO2?
• What is the independent variable?
• What is the dependent variable?
• Design your experiment
– Write a hypothesis
– How would you test for CO2?
– List the procedure
– List the materials you will need
Objective: You will be able to outline the
events of glycolysis.
Do Now:
• Read p. 223
• What is the function of NAD+
The Principle of Redox
• Redox reactions
– Transfer electrons from one reactant to
another by oxidation and reduction
• Electrons from organic compounds
– Are usually first transferred to NAD+, a
coenzyme
2 e– + 2 H+
NAD+
Dehydrogenase
O
NH2
H
C
CH2
O
O–
O
O P
O
H
–
O P O HO
O
N+ Nicotinamide
(oxidized form)
H
OH
HO
CH2
N
H
O
H
HO
N
H
OH
Reduction of NAD+
+ 2[H]
(from food) Oxidation of NADH
NH2
N
N
2 e– + H+
H
Figure 9.4
NADH
H O
C
H
N
NH2
Nicotinamide
(reduced form)
+
The electron transport chain
• Passes electrons in a series of steps
instead of in one explosive reaction
• Uses the energy from the electron transfer
to form ATP
2H
1/
+
2
O2
(from food via NADH)
2 H+ + 2 e–
Controlled
release of
energy for
synthesis of
ATP
Free energy, G
ATP
ATP
ATP
2 e–
1/
2
H+
H2O
Figure 9.5 B
(b) Cellular respiration
2
O2
• An overview of cellular respiration
gure 9.6
Electrons carried
via NADH and
FADH2
Electrons
carried
via NADH
Glycolsis
Pyruvate
Glucose
Cytosol
ATP
Substrate-level
phosphorylation
Citric
acid
cycle
Oxidative
phosphorylation:
electron
transport and
chemiosmosis
Mitochondrion
ATP
Substrate-level
phosphorylation
ATP
Oxidative
phosphorylation
Glycolysis
ATP
Citric
acid
cycle
Oxidative
phosphorylation
ATP
ATP
Energy investment phase
Glucose
2 ATP + 2
P
used
2 ATP
Energy payoff phase
4 ADP + 4
P
2 NAD+ + 4 e- + 4 H +
4 ATP
formed
2 NADH
+ 2 H+
2 Pyruvate + 2 H2O
Glucose
4 ATP formed – 2 ATP used
Figure 9.8
2 NAD+ + 4 e– + 4 H +
2 Pyruvate + 2 H2O
2 ATP
2 NADH
+ 2 H+
Occurs in the cytosol
Splits glucose into two pyruvate molecules
The first phase requires the addition of 2 ATP
molecules to start the reaction
The second phase yields 4 ATP and 2 NADH.
The net yield of glycolysis is 2 ATP and 2
NADH
Group Activity
• Your objective is to design a screenplay
about glycolysis.
• You will need to create a:
– Glucose character
– NAD+ character
– Something to represent electrons
– Something to represent ATP
CYTOSOL
MITOCHONDRION
NAD+
NADH
+ H+
O–
S
CoA
C
O
2
C
C
O
O
CH3
1
3
CH3
Pyruvate
Transport protein
Figure 9.10
Acetyle CoA
CO2
Coenzyme A
Citric Acid Cycle
• Completes the energy-yielding oxidation of
organic molecules
• Takes place in the matrix of the
mitochondrion
Pyruvate
(from glycolysis,
2 molecules per glucose)
Glycolysis
Citric
acid
cycle
ATP
ATP
Oxidative
phosphorylation
ATP
CO2
CoA
NADH
+ 3 H+
Acetyle CoA
CoA
CoA
Citric
acid
cycle
2 CO2
3 NAD+
FADH2
FAD
3 NADH
+ 3 H+
ADP + P i
ATP
Figure 9.11
The Citric Acid Cycle
Occurs in the matrix of the mitochondria
Acetyl CoA enters the cycle and is
completely broken down into CO2
Cycle occurs once for each CoA molecule
A total of 1 ATP, 3NADH, and 1 FADH2
are produced for each turn
2 molecules of CO2 is released as waste
per turn
Objective: You will be able discuss the
significance of the ETC.
Do Now:
• Read “Electron Transport” p. 228-229
• What is the energy of the electrons directly
used for?
NADH and FADH2
• Donate electrons to the electron transport
chain, which powers ATP synthesis via
oxidative phosphorylation
NADH
50
FADH2
40
I
FMN
Fe•S
Free energy (G) relative to O2 (kcl/mol)
Fe•S
Electron
Transport
Chain
Multiprotein
complexes
FAD
II
O
III
Cyt b
30
Fe•S
Cyt c1
IV
Cyt c
Cyt a
Cyt a3
20
10
0
Figure 9.13
2 H + + 12
O2
H2 O
Figure 9–7 Electron Transport Chain
Section 9-2
Electron Transport
Hydrogen Ion Movement
Channel
Mitochondrion
Intermembrane
Space
ATP synthase
Inner
Membrane
Matrix
ATP Production