Cellular Respiration

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Cellular Respiration

• Regular Biology

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What is Cellular Respiration?

• Step-by-step breakdown of high-energy glucose
  molecules to release energy
• Takes place day and night in all living cells
• Occurs in stages, controlled by enzymes

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Where does it occur?

• In the Cell
• Mitochondrion
• Outer Membrane
• Inner Membrane

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Different types of Cellular Respiration

• Anaerobic respiration
• Usually occurs when there is no oxygen available
• When partially breaking down glucose, this
  process releases a very small amount of energy.

• Aerobic respiration
• Occurs in the presence of oxygen
• When chemically breaking down glucose completely,
  this process releases large amounts energy

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Stage 1 Glycolysis

• means "splitting sugars" .6 carbon glucose is
  split into two 3 carbon molecules (pyruvate)
• Occurs in the cytoplasm of cells
• With or Without O2 not required (anaerobic)
• Some ATP produced
• Net yield 2 ATPs

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The Krebs Cycle(a.k.a. citric acid cycle)

• Occurs in the mitochondria
• O2 required (aerobic)
• CO2 (waste)
• Some ATP produced
• Net yield 2 ATPs

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SUMMARY OF THE KREBS CYCLE
6 NADH
GLYCOLYSIS
2 FADH2
CoA
Krebs cycle
CO2
acetyl coenzyme A
2 ATP
electron transport chain
1.
citric acid
oxaloacetic acid
NADH
NAD
NADH
NAD
2.
CO2
6.
a-ketoglutaric acid
malic acid
3.
CO2
FADH2
FAD
NADH
NAD
5.
ADP
4.
a-ketoglutaric acid derivative
succinic acid
ATP
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Electron Transport Chain

• series of electron carriers in the membrane of
  the mitochondria
• Occurs in the inner membrane of mitochondria
• O2 required (aerobic)
• A lot of ATP produced
• Net yield 32 ATPs

Krebs Cycle
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mitochondrion
GLYCOLYSIS
KREBS CYCLE
inner membrane
ELECTRON TRANSPORT CHAIN
inner compartment
32 ATP
H2O
O2
outer compartment
outer compartment
ATP SYNTHESIS
H
H
H
H
H
H
H
H
inner membrane
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
NADH
H
ATP synthesis
NAD
2 H 1/2 O2
ADP P
inner compartment
H2O
ATP
ELECTRON TRANSPORT CHAIN
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Cellular RespirationReview...
Q. Where does each Stage occur?

• 3 Stages
• Stage 1 Glycolysis
• O2 not required (anaerobic)
• Some ATP produced
• Stage 2 Krebs Cycle
• O2 required (aerobic)
• Some ATP produced
• Stage 3 Electron Transport System
• O2 required (aerobic)
• Much ATP produced

2 ATPs
2 ATPs
32 ATPs
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products
reactants
GLYCOLYSIS
glucose
2 ATP
Insert 1 Glucose
2 energy tokens
2 NADH
GLYCOLYSIS
cytosol mitochondrion
(ATP)
glucose derivatives
-
carbon dioxide
2 NADH
2 energy tokens
carbon dioxide
-
KREBS CYCLE
KREBS CYCLE
6 NADH
-
-
2 ATP
2 FADH2
-
32 energy tokens
-
-
ELECTRON TRANSPORT CHAIN
ELECTRON TRANSPORT CHAIN
-
32 ATP
Oxygen
Water
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Aerobic Respiration

• Oxygen combines with glucose to convert it into
  energy
• Releasing carbon dioxide and water as waste
  products.
• glucose oxygen ? carbon dioxide water lots
  of heat energy

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Anaerobic Respiration

• Occurs if there is a lack of oxygen available for
  aerobic respiration
• Glucose is incompletely broken down
• In this type of respiration a lot less energy is
  produced and most of it is lost as heat.

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Anaerobic Energy Production Fermentation

• Lactic Acid
• Formed mainly by animal muscle cells
• Occurs in some unicellular organisms
• Glucose ? lactic acid a tiny amount of heat
  energy

• Alcoholic Fermentation
• Yeast cells, Bacteria
• Glucose ? alcohol carbon dioxide a tiny
  amount of heat energy

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Summary Aerobic Anaerobic

• Similarities
• Glucose is broken down.
• Carbon dioxide is released.
• Energy is liberated.
• Differences