Cellular Respiration

Hypothesize why there are more mitochondria in people with Luft syndrome. Explain your reasoning.

Aerobic Cellular Respiration extracts energy from food in the presence of oxygen energy is used to synthesize ATP from ADP and Pi eukaryotes & prokaryotes that are obligate aerobes undergo Cellular respiration

The Overall Equation Image from: http://factfictionfancy.wordpress.com/2010/01/05/photosynthesis/

Note the outline of the mitochondria in the background of the figure of the next slide… Which step of cellular respiration takes place outside of the mitochondria? Check your diagram and label of the mitochondria with the one found on slide 8.

Cellular Respiration

“The Powerhouse” Image from: http://micro.magnet.fsu.edu/cells/mitochondria/mitochondria.html

Aerobic Cellular Respiration 4 stages: Glycolysis Pyruvate oxidation (Transition stage) Citric acid cycle Electron transport Chain & oxidative phosphorylation

Note the graphic on the next slide and consider: What happens to all of the carbon molecules in sugar? At what stage of Cellular Respiration is most of the ATP made? Note how many carbon dioxide and water molecules are created and how many oxygen molecules are required. How do these numbers relate to the chemical equation?

6 Carbons Glucose sugar Electron Transport Chain 32 ATP 6O2 6H2O C Pyruvate oxidation CO2 2 Citric Acid Cycle 2 ATP CO2 C 4 C 2 ATP Glycolysis C

Overall view of C.R. Image from: http://www.instruction.greenriver.edu/kmarr/Biology%20211/Lecture%2 0Notes/Cellular%20Respiration%20Webpage/Respiration%20Web%20 Notes.html

Make note of where each stage of CR takes place Make note of where each stage of CR takes place. You may want to add that information to your diagram of the mitochondria.

1. Glycolysis takes place in cytoplasm enzymes break down one molecule of glucose into two molecules of pyruvate some ATP and NADH are produced

2. Pyruvate Oxidation (transition stage) occurs in the mitochondria pyruvate is transported (via carrier protein) into mitochondria and is oxidized, forming acetyl-CoA CO2 and NADH are produced

3. Citric Acid (Krebs) Cycle takes place in mitochondria acetyl-CoA enters a cycle and is completely oxidized to CO2 ATP, NADH and FADH2 are produced

4. Electron Transport… takes place in mitochondria the NADH and FADH2 from the first 3 stages are oxidized H2O and a large amount of ATP is produced (32-34)

Image from: http://www. instruction. greenriver Image from: http://www.instruction.greenriver.edu/kmarr/Biology%20211/Lecture%2 0Notes/Cellular%20Respiration%20Webpage/Respiration%20Web%20 Notes.html

ATP can be produced in two ways: 1. Substrate-level phosphorylation - catalyzed by a kinase - phosphate is transferred directly from a substrate (Image from: http://www.bio.miami.edu/~cmallery/150/makeatp/SLP.jpg

2. Oxidative phosphorylation catalyzed by ATP synthase process uses energy transferred indirectly from a series of redox reactions (Image from: http://www.sparknotes.com/biology/cellrespiration/oxidativephosphorylation/section3.rhtml)

What if there is no O2? many organisms can extract energy from food without using oxygen using anaerobic respiration and fermentation much lower amount of energy release in anaerobic pathways

Anaerobic Respiration We know what obligate aerobes are… What about… obligate anaerobes? facultative anaerobes? Obligate anaerobes - bacteria that cause botulism, tetanus, protist Trichonympha Facultative anaerobes - yeast, E. coli bacteria that live in our gut

Write a three sentence summary of Cellular Respiration.