Cellular Respiration CHAPTER 9
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Transcript of Cellular Respiration CHAPTER 9
Cellular RespirationCHAPTER 9
INTRO
• Fast and slow twitch muscles
What kind of runner are you?
• SLOW-TWITCH
• LONG DISTANCE RUNNING
• for repeated long contractions
• FAST-TWITCH
• SPRINTING or WEIGHT LIFTING
• Contract more quickly and powerfully
What makes these muscle fibers so different?
• SLOW TWITCH
• breaks down glucose to get ATP AEROBICALLY (using oxygen)
• FAST TWITCH
• breaks down glucose to get ATP ANAEROBICALLY(not using oxygen)
SLOW-TWITCH MUSCLES
• 1. Thin fibers• 2. have many
mitochondria• Many
myoglobin (lots of hemoglobin in muscle fibers)
FAST-TWITCH MUSCLES
• Thicker fibers
• Fewer mitochondria
• Less myoglobin
• (white meat)
• Chickens use their legs (red meat) for walking and standing for large periods of time,
• while their wings (white meat) are used for brief bursts of activity
Video of Fast and Slow-Twitch Muscles
• Teachers' Domain: The Powerhouse of the Cell
Big Question for Chapter 9
• How do our cells obtain O2
for cellular respiration and dispose of CO2?
• Respiratory System
Respiratory System
• Air intake
Nose
1. mouth
2. Larynx (Voice Box)
• Sound production
• Protection of trachea
Houses epiglottis
3. Vocal chords
• Flaps that vibrate as air goes past them.
• larynx video
4. Trachea
Windpipe
20 rings of
cartilage
5. Right Lung-shorter, broader, larger than left lung
• CT Scan
• X-ray Exchange air rich in CO2
with air rich in O2
6. Bronchioles
• Small branches of airways in lungs
Note Blood Vessel and Bronchiole and Alveoli Closeness
7. Alveoli
• Grape-like clusters of air sacs that exchange with blood vessels carbon dioxide and oxygen
How the Lungs Work - What
Happens When You Breathe Video -
About.com
8. Bronchi
• Large air tubes branch from trachea to lungs
9. Esophagus
• Tube that connects pharynx with stomach
• Glands in it produce mucus to help food slide down
10. Epiglottis
• Flap to control food from going to lungs Swallowing Animation
11. Pharynx
• Throat
• Propels food when swallowing into esophagus
12. Left Lung
• See collapse of left lung
• Smaller due to being on the same side as the heart
Diaphragm
• Muscle at base of lungs to move air in and out of lungs
• How do our bodies burn glucose for energy?
• One gram of glucose when burned in the presence of oxygen releases 3811 calories of heat energy.
calorie
• Amount of energy needed to raise the temperature of one gram of water one degree Celsius.
Calorie
• Calorie = 1000 calories
• = 1 kilocalorie
Calories on food labels are actually
kilocalories
• How does the amount of energy released in glycolysis compare to burning one gram of glucose?
• Small amount (around 3.5% the amount from burning)
• So….. 3811 X 3.5% =• 133.4 calories
Cellular Respiration
• 1. Glycolysis
• 2. Krebs cycle
• 3. ETC and chemiosmosis
Cellular Respiration
• C6H12O6 + 6O2 --> 6CO2 + 6H2O + ~38 ATP
• Glucose + oxygen --> carbon+ water +energy• dioxide
In the mitochondrion
Glycolysis Animation: How Glycolysis Works
glucose
Pyruvic acid
Starts with 2 ATP
Makes 4 ATP
Nets: 2 ATP
NAD+
• An electron carrier• Nicotinamide adenine
dinucleotide• Accepts electrons (H+)
to form NADH
e-
e-
Electron Carrier
• A.k.a. “hydrogen carrier”
• Electron taxi cab NADH
(full)
NAD+(empty)
e-
NAD+ NADHe- carrier
Glycolysis is Anaerobic
• Without oxygen
oxygen
Only catch...
• NAD+ is used up in glycolysis
• So a cell needs a way to regenerate it (to keep glycolysis going)
How does NADH regenerate back to NAD+?
• The process of fermentation.
• It loses the electrons of NADH to form NAD+ again.
• Remember the yeast lab?
Sing or Simulate
• Glucose, Glucose SONG
• See Teacher Tube
END OF GLYCOLYSIS
• How much of the energy in glucose is still unused?
• 90% Doesn’t seem very efficient, does it?
Now What, Pyruvic Acid?
• Fermentation
• Anaerobic – no oxygen
• In cytoplasm
• Krebs Cycle
• Aerobic –needs oxygen
• In mitochondria
Fermentation
sauerkraut
cheese
bread
wine
OK, if you are yeast...
• Making
2 ATP from glycolysis is enough
Yeast Acting on Pyruvic Acid
• Ethanol is released as a waste product O
o
o
o
NAD+
CO2
Alcoholic Fermentation
• Pyruvic acid + NADH alcohol + CO2 + NAD+
Lactic Acid in Bacteria
• Used in dairy industry to make cheese and yogurt
Lactic Acid Fermentation
• Pyruvic acid + NADH lactic acid + NAD+
Why must oxygen be kept out of the wine and beer vats?
• If oxygen is present, the pyruvic acid will make CO2 and water.
• If oxygen is not present, yeast and bacteria will make ethanol and CO2.
CONTRAST
• ANAEROBIC
• Does not use oxygen
• In the cytoplasm
EX: Glycolysis
Fermentation
• AEROBIC
• Uses oxygen
• In the mitochondrion
• EX: Krebs cycle
ETC and chemiosmosis
#3 CONTRAST
• Respiration• Really mean
breathing• Means of getting
oxygen into body and carbon dioxide out
• Cellular Respiration
• energy-releasing pathway within the cell (mitochondrion)
#4 Pyruvic Acid (Pyruvate)
In order to further break down pyruvic acid we need
oxygen.
2 2 34
Cytoplasm
CO2 CO2
#5 Mitochondrion
• Organelle that can use oxygen for cellular respiration.
“Grooming” Pyruvic Acid Haircut and Conditioning
“HAIRCUT”
As NADH is reduced to NAD+
pyruvic acid is oxidized (carbon atom removed as CO2)
“CONDITIONING”
Coenzyme A (from B vitamin) joins the 2-c fragment
MAKES-Acetyl Coenzyme
A or CoA
#6
#7
Cut, Groom and Krebs Cycle Animation
• krebstca
• animation
Ready to GO
• The Acetyl-CoA is now ready to enter the Krebs cycle
Hans Krebs (1900-1981)Yeah, he got a Nobel Prize, too
#4- #8 Krebs Cycle
• Also known as “citric acid cycle”
#9
Cellular Respiration
• Respiration animation
• Cellular respiration
CONTRAST
• AEROBIC
• Does use oxygen
Glycolysis
Fermentation
• ANAEROBIC
• Does not oxygen
• In the mitochondrion
• Krebs cycle
• ETC and chemiosmosis
ATP Synthase
• VCAC: Cellular Processes: ATP Synthase: The Movie (Cool)
Where does it all come from?
•1 NADH = 3 ATP
•1 FADH2 = 2 ATP
ChemiosmosisPowers Most of ATP Produced
• Glycolysis -2 ATP
• Krebs Cycle - 2 ATP
• Chemiosmosis/ ETC - 34 ATP
• TOTAL 38 ATP from one glucose molecule
ETC
• Electron Transport Chain
• VCAC: Cellular Processes: Electron Transport Chain
• Or krebstca
Where is the ETC located?
• Inner membrane of the mitochondrion
What gets made via the ETC?
• 1. electrons + H+ + Oxygen = water
• 2. H+ ions go across the inner membrane and build up in the inner membrane space
• H+ ions go through ATP synthase to generate ATP
e-e- e-
ATP ADP + P
e-
ATP SYNTHASE
• H+ ions move through this enzyme to generate energy for P to join ADP to make ADP
Chemiosmosis and ETC
• H+ ions can only pass through a special port ATP synthase (see knobs on cristae)
ETC Animation
• Krebstca (clear, nice animation)
• Electron transport system (very simple)
• VCAC: Cellular Processes: Electron Transport Chain click on THE MOVIE)
• ETC (nice from McGraw Hill)
ATP GRAND TOTALS
• Glycolysis produces 2 ATP• Krebs cycle produces 2 ATP• ETC and chemiosmosis produces 34 ATP
GRAND TOTAL 38 ATP from one glucose molecule
CONTRAST CHART
• Photosynthesis• Makes sugars for
food energy• Chloroplast• React: CO2 and H2O• Prod: C6H12O6 and O2
• EQUATION:
6 CO2 and 6 H2O
6 O2 + C6H12O6
• Cellular Respiration• Energy released
• Mitochondrion• C6H12O6 and O2
• CO2 and H2O• EQUATION:• 6 O2 + C6H12O6 6
CO2 and 6 H2O