Transcript 20121016083538

Cellular Respiration
Harvesting Chemical Energy
ATP
Regents Biology
2007-2008
 Respiration
 Must have enzymes!!!
 C6H12O6 + 6O26CO2 + 6H2O + ATP
 Photosynthesis
 Must have enzymes & light &

chlorophyll!!!!
6CO2 + 6H2O  C6H12O6 + 6O2
Regents Biology
Energy needs of life
 Animals are energy consumers

What do we need energy for?
 synthesis (building)
 reproduction
 active transport (pumping)
 movement
 temperature control (making heat)
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Where do we get energy?
 Energy is stored in organic molecules
carbohydrates, fats, proteins
Animals eat these organic molecules  food
 digest food to get


 fuels for energy (ATP)
 raw materials for building more molecules
 carbohydrates, fats, proteins, nucleic acids
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What is energy in biology?
ATP
Adenosine TriPhosphate
Whoa!
HOT stuff!
Regents Biology
2007-2008
Harvesting energy stored in food
 Cellular respiration

breaking down food to produce ATP
 in mitochondria
 using oxygen

usually digesting glucose
 but could be other sugars,
fats, or proteins
glucose + oxygen  carbon + water + energy
dioxide
C6H12O6 +
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6O2
 6CO2 + 6H2O + ATP + heat
What do we need to make energy?
 The “Furnace” for making energy

mitochondria
Make ATP!
Make ATP!
All I do all day…
And no one
even notices!
 Fuel

food
 carbohydrates,
fats, proteins
food
 The Helpers

oxygen
 “aerobic”

enzymes
enzymes
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O2
ATP
Mitochondria are everywhere!!
animal cells
plant cells
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“Burn fuels” to make energy
combustion
making heat energy by burning fuels in one step
fuel
(carbohydrates)
O2
CO2 + H2O + heat
aerobic respiration
making ATP energy (& some heat) by burning fuels
in many small steps
ATP
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food
(carbohydrates)
O2
CO2 + H2O + ATP (+ heat)
Using ATP to do work?
Can’t store ATP
 too unstable
 only used in cell
that produces it
 only short term
energy storage
 carbohydrates & fats
are long term
energy storage
Whoa!
Pass me the
glucose & oxygen!
Regents Biology
ATP
Adenosine TriPhosphate
work
Adenosine DiPhosphate
ADP + P
A working muscle recycles over
10 million ATPs per second
A Body’s Energy Budget
eat
food
ATP
synthesis
(building)
storage
Regents Biology
{
{
{
• energy needed
even at rest
• activity
• temperature
control
• growth
• reproduction
• repair
• glycogen
(animal starch)
• fat
What if oxygen is missing?
 Can’t complete aerobic respiration

Fermentation (anaerobic respiration)
 alcohol fermentation
 yeast
glucose  ATP + CO2+ alcohol
 make beer, wine, bread

 lactic acid fermentation
 bacteria, animals
glucose  ATP + lactic acid
 bacteria make yogurt
 animals feel muscle fatigue

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but only make a
little bit of ATP!
O2
Glycolysis p. 97
 Cytoplasm
 2ATP-activation energy
 Glucose 2 pyruvic acids (pyruvates)
 2 NAD2NADH
 4 ADP4 ATP(substrate level
phosphorylation)
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Oxidation of pyruvic acid p. 98
 Mitochondria
 2 pyruvic acid2 acetyl
 2 NAD2 NADH
 2 CO2 given off
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Citric Acid Cycle (Krebs Cycle)
p.99
 occurs in matrix







CoA ushers acetyl in
Acetyl joins with O acid to form citric acid
2 CO2 are released
1 ATP made (substrate level phosphorylation)
3 NADH
1FADH2
Turns twice
Regents Biology
Electron Transport Chain p.100
 Peter Mitchell Chemiosmosis
 Proton Gradient
 Oxidative phosphorylation
 Occurs in cristae
 NADH and FADH2 drop off electrons
 As electrons move down, protons are

pumped into intermembrane space
Protons rush through ATP Synthase
and make 36 ATP
Regents Biology