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Unit II, Chapter 25 pg 950-971
selected portions
Glycolysis, Krebs cycle, Electron
Transport Chain, ATP stores potential
energy
Some cell processes req’ring energy
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Na+/K+ pump
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(as any active transport process)
Power stroke of skeletal muscle
Glycolysis
Flagellar motility
Microtubule movement during cell division
ATP is a high energy molecule
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Phosphorylation of ADP increase its PE
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Breaking the bond between the 2nd and 3rd
P group results in energy liberation
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Forming bonds _____________________
ATP  ADP
ATPase – enzyme, catalyzes _________
bond, creating ADP
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________ ________ is used do work
Linking catabolism & anabolism
Oxidation & reduction rxns
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_______________- removal of electrons, or H+
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decrease potential energy content
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Usually exergonic – releases energy
Cmpds such as glucose (reduced) have lots of H 
contain more chemical P.E. than the oxidized cmpds
________________- addition of e- or H+
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Oxidation of glucose = cellular respiration
increase of energy content of molecule
Oxidation & reduction rxns are always coupled
Cellular respiration
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___________________ to produce ATP
To attach a phosphate group to ADP to produce
ATP ____________ energy
Series 4 reactions in presence of oxygen produces
more ATP than when oxygen is absent:
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Glycolysis
Acetyl Coenzyme A formation
Krebs cycle
Electron Transport Chain
Cellular respiration (2)
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__________ cellular respiration- oxygen absent
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glucose breakdown, catabolic rxns  2 pyruvic acid
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This process is called glycolysis
1 glucose yields 2 ATP
happens in cytosol
____________- in presence of oxygen
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Glycolysis + rxns 6 CO2 + 6 H2O & energy
Generates heat and 36-38 ATP
happens in mitochondria
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Overview of
cell respiration
(oxidation of
glucose)
Glycolysis – 10 steps, fig 25.4
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Rxn generates 4 ATP & 2 pyruvic acid*
Net gain:
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2 ATP = metabolic energy
2 NADH = intermediate for e- transport chain
2 H+ = intermediate for e- transport chain
* Oxygen _______, pyruvic acid  mitochondria
for Krebs cycle and ETC
* Oxygen _______, pyruvic acid likely converted
to lactic acid via anaerobic resp in cytosol
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Lactic acid  liver to be converted to glucose
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Fate of pyruvic acid
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Oxygen present 
mitochondria,
becomes CoA and
goes to Krebs
Oxygen absent –
converted to lactic
acid in cytosol
(lactic acid 
bloodstream  liver
where it is converted
back to pyruvic acid)
3 main results of Krebs cycle
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reduced coenzymes NADH + H+ and
FADH2, containing ________________
GTP, which ___________ to make ATP
CO2  bloodstream and ________ at lungs
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6 CO2 made for every glucose
So, how do we get 36-38 ATP?....
1 glucose yields 36-38 ATP
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3 NADH + 3 H+  e- transport = 9 ATP
1 FADH2  e- transport = 2 ATP
1 ATP from GTP conversion
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Multiply the above results by 2 because 2 Acetyl
CoA come from one glucose!
2 NADH produced during glycolysis produce 4-6
ATP
2 NADH produced during Acetyl CoA formation
also produce 6 ATP
2 ATP from glycolysis
Electron Transport Chain
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Series of electron carriers (proteins called
_________) in the inner mitochondrial membrane
Each carrier is reduced then oxidized
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Rxns are exergonic & energy is _____ to make ATP
In aerobic resp, final e- acceptor is oxygen (gets
reduced  H2O)
_____________- links chemical rxn w/H+ pump
Electron Transport Chain (2)
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Proton pumps send H+ from matrix to
intermembrane space
Creates a gradient, H+ gets build up in the
intermembrane space
H+ flow back to the matrix (by proton
motive force) through a channel in ATP
synthase
ATP synthase adds a P to ADP  ATP
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Summary of cellular
respiration, fig 25.10
See also table 25.1
page 962
Proteins & fats  glucose
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Amino acids, glycerol, & lactic acid can be
converted to glucose – ____________________
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Process by which glucose is created from noncarbohydrate sources
Stimulated by
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_______________ from adrenal cortex
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Also causes proteins  amino acids
_______________ from pancreas
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