Interest Grabber

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Interest Grabber
Section 9-1

• Feel the Burn
• Do you like to run, bike, or swim? These all are
  good ways to exercise. When you exercise, your
  body uses oxygen to get energy from glucose,a
  six-carbon sugar.

1. How does your body feel at the start of
exercise, such as a long, slowrun? How do you
feel 1 minute into the run 10 minutes into the
run? 2. What do you think is happening in your
cells to cause the changesin how you
feel? 3. Think about running as fast as you can
for 100 meters. Could youkeep up this pace for a
much longer distance? Explain your answer.
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Section Outline
Section 9-1

• 91 Chemical Pathways
• A. Chemical Energy and Food
• B. Overview of Cellular Respiration
• C. Glycolysis
• 1. ATP Production
• 2. NADH Production
• D. Fermentation
• 1. Alcoholic Fermentation
• 2. Lactic Acid Fermentation

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Chemical Energy and Food

• A calorie is the amount of energy needed to raise
  the temperature of 1 gram of water 1 degree
  Celsius.
• A Calorie is equal to 1000 calories.
• One gram of glucose releases 3811 calories of
  heat energy.
• Aerobic process that requires oxygen.
• Anaerobic process that does not require oxygen.

Fast Food Calorie Counter
http//www.washingtonpost.com/wp-srv/flash/health/
caloriecounter/counter.htm
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Mitochondria

• Mitochondria are membrane-enclosed organelles
  distributed through the cytoplasm of most
  eukaryotic cells. There main function is the
  conversion of the potential energy of food into
  ATP.
• Mitochondria have
• An outer membrane encloses the entire structure.
• An inner membrane that encloses a fluid-filled
  matrix.
• Between the two is the intermembrane space
• The inner membrane is elaborately folded with
  shelf-like cristae projecting into the matrix
• A small number (5-10) circular molecules of DNA

http//users.rcn.com/jkimball.ma.ultranet/BiologyP
ages/C/CellularRespiration.html
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Mitochondrion
http//www.jdaross.mcmail.com/mitochon.htm
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Parts of the Mitochondrion

• The Matrix
• -Contains a mixture of enzymes that catalyze
  the respiration of pyruvic acid.
• Here pyruvic acid is
• Oxidized by NAD producing NADH H
• Decarboxylated producing CO2 and a 2-Carbon
  fragment of Acetate bound to coenzyme A forming
  acetyl-CoA

• The Outer Membrane
• -Contains many membrane proteins that form
  channels through which a variety of molecules and
  ions move in and out.
• The Inner Membrane
• -Contains five membrane proteins
• NADH dehydrogenase
• Succinate Dehydrogenase
• Cytochrome c Reductase
• Cytoschrome c Oxidase
• ATP Synthase

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• - NAD (nicotinamide adenine dinucleotide) is an
  electron carrier that accepts a pair of
  high-energy electrons.
• NADH holds the electrons until they can be
  transferred to other molecules.
• Pyruvic acid is a three carbon product of the
  metabolism of a glucose (6-Carbon) molecule
• Lactic Acid is a three carbon product of Lactic
  Acid Fermentation when Pyruvic Acid gains a
  hydrogen atom.

Cellular Respiration Website
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Glycolysis Sweet Break

• C6H12O6 2 NAD ? 2C3H4O3 2 NADH 2 H

• Glycolysis is the anaerobic catabolism (break
  down) of glucose.
• It occurs in virtually all cells.
• In eukaryotes, it occurs in the cytoplasm.
• The free energy stored in 2 molecules of pyruvic
  acid is somewhat less than that in the original
  glucose molecule.
• Some of this difference is captured in 2
  molecules of ATP

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Figure 93 Glycolysis
Section 9-1
Glucose
2 Pyruvic acid
To the electron transport chain
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Figure 93 Glycolysis
Section 9-1
Glucose
2 Pyruvic acid
To the electron transport chain
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Figure 93 Glycolysis
Section 9-1
Glucose
2 Pyruvic acid
To the electron transport chain
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Fermentation

• Fermentation releases energy from food molecules
  by producting ATP in the absence of oxygen.
• Cells convert NADH to NAD by passing high-energy
  electrons back to pyruvic acid. This action
  converts NADH back into the electron carrier
  NAD, allowing glycolysis to continue producing a
  steady supply of ATP.
• -Fermentation is anaerobic (does not require
  oxygen).

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Alcoholic Fermentation

• Alcohol fermentation is done by yeast and some
  kinds of bacteria.
• These microorganisms convert sugars in ethyl
  alcohol and carbon dioxide. Alcoholic
  fermentation begins after glucose enters the
  cell.
• The glucose is broken down into pyruvic acid.
  This pyruvic acid is then converted to CO2,
  ethanol, and energy for the cell.
• Pyruvic Acid NADH ? alcohol CO2 NAD
• Ex Baking Bread Wine making

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Lactic Acid FermentationAKA Feel the Burn

• If there is a lack of oxygen present in the cell,
  H build up inside the cell making it acidic. To
  prevent this rise pyruvic acid accepts H forming
  lactic acid.
• Pyruvic acid NADH ? Lactic Acid NAD
• The product NAD then can take part in Glycolysis
  to release 2 more ATP molecules.
• Ex Lactic acid is produced in our muscles during
  rapid exercise. Other examples include cheese,
  buttermilk, sour cream, pickles and sauerkraut.

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Figure 94 Lactic Acid Fermentation
Section 9-1
Lactic acid
Glucose
Pyruvic acid
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Figure 94 Lactic Acid Fermentation
Section 9-1
Lactic acid
Glucose
Pyruvic acid
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Figure 94 Lactic Acid Fermentation
Section 9-1
Lactic acid
Glucose
Pyruvic acid
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Interest Grabber
Section 9-2

• Rolling and Folding
• Some of the steps in cellular respiration take
  place in the membrane inside the cell structure
  called the mitochondrion, which has a folded
  inner membrane. What purpose do these folds
  serve?
• To find out the answer to this question, perform
  this activity.

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Interest Grabber continued
Section 9-2

• 1. Obtain two sheets of paper and a metric ruler.
  What is the surface area of the paper?
• 2. Roll one sheet of paper into a tube
  lengthwise. What is the surface area of the
  rolled paper?
• 3. Fold the second sheet of paper into a fan.
  Then, roll the firstsheet of paper around the
  folded paper so it is inside the rolled
  paper.What has happened to the surface area of
  the inside of the rolled paper?
• 4. What would be the value of increasing the
  surface area of the membrane inside a
  mitochondrion?

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Section Outline
Section 9-2

• 92 The Krebs Cycle and Electron Transport
• A. The Krebs Cycle
• B. Electron Transport
• C. The Totals
• D. Energy and Exercise
• 1. Quick Energy
• 2. Long-Term Energy
• E. Comparing Photosynthesis and Cellular
  Respiration

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Chemical Pathways
Section 9-1
Glucose
Krebs cycle
Electrontransport
Glycolysis
Alcohol or lactic acid
Fermentation (without oxygen)
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Figure 92 Cellular Respiration An Overview
Section 9-1
Mitochondrion
Electrons carried in NADH
Electrons carried in NADH and FADH2
Pyruvic acid
Glucose
Electron Transport Chain
Krebs Cycle
Glycolysis
Mitochondrion
Cytoplasm
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Flowchart
Section 9-2
Cellular Respiration
Glucose(C6H1206) Oxygen(02)
Glycolysis
KrebsCycle
ElectronTransportChain
Carbon Dioxide (CO2) Water (H2O)
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The Krebs Cycle AKA Citric Acid Cycle

• This set of reactions is named after Hans Kreb,
  the discoverer.
• Unlike glycolysis, the Krebs cycle does not
  produce a final end product. Instead, it is a
  continuous series of reactions.
• To begin, the pyruvic acid produced during
  glycolysis travels from the cytoplasm to the
  mitochondria.
• 1st The pyruvic acid is broken down into Carbon
  Dioxide and a 2-Carbon compound called acetic
  acid.
• 2nd the Acetic Acid binds to a carrier molecule
  called coenzyme A (CoA), and reacts with a
  4-carbon compound to produce citric acid, a
  6-Carbon compound.

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Krebs Continued

• Inside the Krebs Cycle are nine reactions and
  nine intermediates.
• - At 2 places CO2 is released.
• - At 4 places a pair of high-energy electrons
  are accepted by electron carriers, changing NAD
  to NADH and FAD and FADH2
• - At one place a molecule of GDP (Similar to
  ADP) is converted to GTP (Similar to ATP). The
  GTP may then be used to make ATP.
• Summary
• 2 Carbon atoms added from the breakdown of
  pyruvic acid
• 2 Carbon atoms removed (in 2 molecules of CO2)
• 3 Molecules of NAD converted to NADH
• 1 Molecule of FAD converted to FADH2
• 1 Molecule of GDP converted to GTP

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Figure 96 The Krebs Cycle
Section 9-2
Citric Acid Production
Mitochondrion
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Figure 96 The Krebs Cycle
Section 9-2
Citric Acid Production
Mitochondrion
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Electron Transport Chain

• The Electron Transport Chain uses the high-energy
  electrons from the Krebs cycle to convert ADP
  into ATP.
• High-energy electrons from NADH and FADH2, are
  passed along the electron transport chain.
• In eukaryotes, the electron transport chain is
  composed of a series of carrier proteins located
  in the inner membrane of the _____________________
  _________.
• In prokaryotes, the same chain is located in the
  _________________________________.

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Steps 1 NADH
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Step 2 FADH2
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Step 3 ATP Synthase
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Key Points

• ______________ are translocated ________________
  the membrane, from the matrix to the
  intermembrane space
• _________________ are transported along the
  membrane, through a series of protein carriers
• _________________ is the terminal electron
  acceptor, combining with electrons and H ions to
  produce ___________________
• As NADH delivers more H and electrons into the
  ETS, the proton gradient increases, with H
  building up outside the inner mitochondrial
  membrane, and OH- inside the membrane.

http//www.sp.uconn.edu/terry/images/anim/ETS.htm
l
http//www.science.smith.edu/departments/Biology/B
io231/etc.html
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Figure 97 Electron Transport Chain
Section 9-2
__________________
____________________
Channel
Mitochondrion
Intermembrane Space
_______________
Inner Membrane
Matrix
ATP Production
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Video Contents
Video Contents

• Click a hyperlink to choose a video.
• Aerobic Respiration
• Glycolysis
• Krebs Cycle, Part 1
• Krebs Cycle, Part 2
• Electron Transport Chain, Part 1
• Electron Transport Chain, Part 2

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Video 1
Video 1
Aerobic Respiration

• Click the image to play the video segment.

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Video 2
Video 2
Glycolysis

• Click the image to play the video segment.

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Video 3
Video 3
Krebs Cycle, Part 1

• Click the image to play the video segment.

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Video 4
Video 4
Krebs Cycle, Part 2

• Click the image to play the video segment.

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Video 5
Video 5
Electron Transport Chain, Part 1

• Click the image to play the video segment.

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Video 6
Video 6
Electron Transport Chain, Part 2

• Click the image to play the video segment.

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Internet
Go Online

• Links from the authors on Creatine
• Share kimchi lab data
• Interactive test
• For links on cellular respiration, go to
  www.SciLinks.org and enter the Web Code as
  follows cbn-3091.
• For links on the Krebs cycle, go to
  www.SciLinks.org and enter the Web Code as
  follows cbn-3092.

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Section 1 Answers
Interest Grabber Answers
1. How does your body feel at the start of
exercise, such as a long, slowrun? How do you
feel 1 minute into the run 10 minutes into the
run? Students may answer that they feel no
fatigue at the start of a run however, after 1
minute and more so after 10 minutes, they are
breathing hard, their heart rate has increased
significantly, and their muscles may hurt.
2. What do you think is happening in your cells
to cause the changesin how you feel? Students
may say that the increase in heart rate and
breathing rate are a response that gets extra
oxygen to the cells. The pain may be attributed
to the cells becoming fatigued. 3. Think about
running as fast as you can for 100 meters. Could
youkeep up this pace for a much longer distance?
Explain your answer. Students may know that very
high levels of performance can be sustained only
very briefly even among the best of athletes.
Students may say that the body runs out of
readily available energy, food, or oxygen, or
that the body builds up too many waste products
in the cells.
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Section 2 Answers
Interest Grabber Answers

• 1. Obtain two sheets of paper and a metric ruler.
  What is the surface area of the paper?
• The area will vary depending on the size of
  paper used. A sheet of notebook paper has an area
  of approximately 600 cm3.
• 2. Roll one sheet of paper into a tube
  lengthwise. What is the surface area of the
  rolled paper?
• The surface area is the same as the original
  sheet of paper.
• 3. Fold the second sheet of paper into a fan.
  Then, roll the firstsheet of paper around the
  folded paper so it is inside the rolled
  paper.What has happened to the surface area of
  the inside of the rolled paper?
• The surface area has increased (surface area of
  rolled paper surface area of folded paper).
• 4. What would be the value of increasing the
  surface area of the membrane inside a
  mitochondrion?
• Increasing the surface area increases the amount
  of space where chemical reactions can take
  place.

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End of Custom Shows

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