1 / 34

Cellular Respiration & Fermentation

Cellular Respiration & Fermentation. How much energy is in food?. When 1 gram of glucose (C 6 H 12 O 6 ) is burned in the presence of oxygen, 3811 calories are released! What is a calorie? The amount of energy needed to raise the temperature of 1 gram of water 1 degree Celsius.

judson
Download Presentation

Cellular Respiration & Fermentation

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Cellular Respiration & Fermentation

  2. How much energy is in food? • When 1 gram of glucose (C6H12O6) is burned in the presence of oxygen, 3811 calories are released! What is a calorie? • The amount of energy needed to raise the temperature of 1 gram of water 1 degree Celsius

  3. Chemical Energy & Food • On a food label, Calories (with a capital “C”) represent kilocalories! • 1 kilocalorie = 1000 calories!

  4. How many calories are in 2 crackers? • 60 • 6,000 • 60,000 • Not enough info. 60,000!

  5. Cellular Respiration • The slow release of energy from glucose We think of “respiration” as breathing! We take in oxygen & exhale carbon dioxide…

  6. Cellular Respiration • Gas exchange occurs at the cellular level to drive cellular respiration! • O2 is a reactant. • CO2 is a waste product. • Breathing is our body’s way of getting these gases into and out of our body to perform cellular respiration!

  7. Cellular Respiration & Fermentation • Methods by which organisms break down food molecules to release energy for life functions

  8. Cellular Respiration & Fermentation • Both processes begin with glycolysis, breaking down glucose into 2 smaller molecules of pyruvate. • From here, whether oxygen is present or not determines the process that happens next!

  9. Cellular Respiration & Fermentation • All organisms must perform some sort of respiration or fermentation in order to obtain energy from storage molecules (food)!

  10. Cellular Respiration • The process that releases energy by breaking down glucose & other food molecules in the presence of oxygen O2 + C6H12O6 CO2 + H2O + ATP Oxygen + Glucose  Carbon Dioxide + Water + Energy

  11. What is the balanced chemical equation for cellular respiration? • 6O2 + C6H12O66CO2 + 6H2O + 36 ATP • 4O2 + C6H12O64CO2 + 4H2O + 16 ATP • 2O2 + C6H12O62CO2 + 2H2O + 4 ATP • All ready balanced! 6O2 + C6H12O66CO2 + 6H2O + 36 ATP

  12. Mitochondria – ENERGY! • Inner membrane is highly folded to increase surface area!

  13. Glycolysis • The process by which 1 molecule of glucose is broken in half to produce 2 molecules (3-carbon) of pyruvate (pyruvic acid) • Occurs in the cytoplasm!

  14. Glycolysis • 10 enzymatic reactions occur during glycolysis! • The 1st half of glycolysis requires 2 ATPs and the 2nd half forms 4 ATPs and 2 NADHs. • Net! There are 2 ATPs and 2 NADHs formed!

  15. Fermentation – Option 1 after Glycolysis! • Occurs when no oxygen is present! • Also called “anaerobic respiration” (means without oxygen) • Turns NADH back into NAD+ so that it can be recycled & glycolysis can continue • Two types: • Alcoholic Fermentation • Lactic Acid Fermentation

  16. Alcoholic Fermentation • Yeast & other microorganisms perform this Pyruvic Acid + NADH  Alcohol + CO2 + NAD+

  17. Alcoholic Fermentation • Used to help us make things like bread & wine!

  18. Lactic Acid Fermentation • In a shortage of oxygen in your muscle cells, it regenerates NAD+, so glycolysis can continue. • Lactic Acid builds up in your muscles, which causes pain & soreness! Pyruvic Acid + NADH  Lactic Acid + NAD+

  19. Lactic Acid Fermentation • Also used by bacteria, which are used to produce yogurt & other foods (like sourdough breads, sauerkraut, pickles, & olives)!

  20. Aerobic Cellular Respiration – Option 2 after Glycolysis! • The remaining 90% of the energy from the glucose molecule that was not used in glycolysis is used in the part of cellular respiration that requires oxygen (aerobic). Glycolysis

  21. Cellular Respiration • Occurs when oxygen is present (aerobic respiration) • Occurs in the mitochondria! • Two parts: • Krebs Cycle • Electron Transport Chain

  22. The Krebs Cycle (Citric Acid Cycle) • Pyruvate is broken down into carbon dioxide molecules in a series of steps that also form ATP, NADH, and FADH2 for use in the Electron Transport Chain! • Occurs in the matrix of the mitochondria!

  23. The Electron Transport Chain • Uses high energy electrons from NADH and FADH2 from Krebs Cycle to build up H+ ions in the intermembrane space • This makes the intermembrane space positive & the matrix negative!

  24. The Electron Transport Chain • The H+ ions will then move through the ATP Synthase to the negative side causing the ATP Synthase to turn. • Each turn brings ADP and a phosphate together to form high energy ATP.

  25. The Krebs Cycle & ETC occur in the mitochondria!

  26. Totals • Cellular Respiration produces 36 ATP molecules! • More ATP is produced with oxygen than without. • Cellular Respiration is more efficient using oxygen!

  27. Energy & Exercise • Running a short race, you use ATP in your muscles & produce new ATP by lactic acid fermentation & cellular respiration!

  28. Energy & Exercise • When sprinting, you produce most of your ATP using lactic acid fermentation, because you have run out of oxygen for the Krebs Cycle! You breathe heavily after a race to rebuild your ATP supply!

  29. Energy & Exercise • When running a long race, you use carbohydrate energy (stored as glycogen) from your muscles & other tissues. • This will give you enough energy for up to 20 minutes of activity! • After using up the glycogen, your body will use fats for energy! • This is why aerobic exercises (like running & swimming) are beneficial for weight control!

  30. Photosynthesis vs. Cellular Respiration • If storing energy is compared to money in a savings account, photosynthesis deposits the energy & cellular respiration withdraws the money! Have you noticed that Cellular Respiration is the reverse reaction of Photosynthesis?!

  31. 6CO2 + 6H2O + Light  6O2 + C6H12O6 • Photosynthesis • Cellular Respiration Photosynthesis!

  32. Photosynthesis vs. Cellular Respiration • PS uses CO2 in the atmosphere, but CR puts it back! • PS releases O2 into the atmosphere, but CR uses O2 to release energy from food! • CR occurs in all eukaryotes & some prokaryotes! • PS occurs only in plants, algae, & some bacteria. Other organisms (heterotrophs) get their energy by consuming other organisms!

More Related