1 / 28

Cellular Respiration

Cellular Respiration. Honors Agriculture Biology. Why are photosynthesis and respiration important in agriculture?.

rachel-puckett
Download Presentation

Cellular Respiration

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 Honors Agriculture Biology

  2. Why are photosynthesis and respiration important in agriculture? • Biomass is all plant and animal matter on the Earth's surface. Harvesting biomass such as crops, trees or dung and using it to generate energy such as heat, electricity or motion, isbioenergy. • Farmers try to maintain a 40:1 ratio of photosynthesis to respiration, thus increasing the amount of biomass stored by the plants. • More Biomass= More Energy

  3. Why is Respiration Important? • Plants use oxygen in the air (or water) to turn their food (glucose) into energy. This process of using oxygen to release energy from food is called cellular respiration

  4. Interest Grabber • What kind of organisms undergo cellular respiration? • All organisms including photosynthetic organisms, undergo cellular respiration as long as oxygen is present

  5. Interest Grabber • How are the products of photosynthesis and respiration related? • The products of photosynthesis are the starting materials for respiration

  6. Cellular Respiration C6H12O6 + 6O2 6CO2 + 6H2O + Energy (ATP)

  7. Cellular Respiration

  8. Photosynthesis Food synthesized (made) Energy from sun stored in glucose CO2 taken in Oxygen given off Produces sugars Requires light Occurs only in the presence of chlorophyll Respiration Food broken down Energy in glucose released CO2 given off Oxygen taken in Produces CO2 and H2O Does not require light Occurs in all living cells Photosynthesis vs. Respiration

  9. Chemical Pathways • Cells don’t “burn” glucose • They gradually release the energy from glucose and other food compounds • The process begins with a pathway called GLYCOLYSIS. • Glycolysis releases only a small amount of energy (net yield of 2 ATP)

  10. Glycolysis • Process in which one molecule of glucose is broken in half • Occurs in the cytoplasm of the cell • This is an anaerobic process • Produces two molecules of pyruvic acid • A 3 carbon compound

  11. Glycolysis • At the pathway’s beginning, 2 molecules of ATP are used up • These 2 molecules should be looked at as an “investment” • Gives the cell 2 net ATP molecules

  12. Glycolysis • This process seems like it doesn’t create very much energy • But…the cells are able to finish the process so fast, that they can create thousands of ATP molecules in just a few milliseconds

  13. Interest Grabber • 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.

  14. Interest Grabber • Obtain two sheets of paper and a metric ruler. What is the surface area of the paper? • Roll one sheet of paper into a tube lengthwise. What is the surface area of the rolled paper? • Fold the second sheet of paper into a fan. Then, roll the first sheet 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? • What would be the value of increasing the surface area of the membrane inside a mitochondrion?

  15. The Krebs Cycle • In the presence of oxygen, pyruvic acid produced in glycolysis passes to the second stage of cellular respiration • The Kreb’s Cycle (also known as the Citric Acid Cycle) occurs in the mitochondria of the cell • Named after Hans Krebs • 1937; he discovered the details of what is now known as the Krebs Cycle

  16. Krebs Cycle • During the Krebs cycle the following occurs • Pyruvic acid is broken down into carbon dioxide in a series of energy-extracting reactions • NADH, FADH2, CO2 and ATP • A total of 2 ATP are created from this stage

  17. Krebs Cycle • Every time you exhale, carbon dioxide is released • This carbon dioxide is produced by the Krebs Cycle • The ATP produced is used for cellular activities

  18. Electron Transport • Electrons passed around during the Krebs Cycle to the electron transport chain • The electron transport chain uses the high-energy electrons from the Krebs Cycle to convert ADP into ATP • A total of 32 ATP are created in the mitochondria during this stage of resp.

  19. Electron Transport Chain

  20. Activity (see handout) • Procedure • Predict (in your lab book) how exercise will affect your body’s production of Carbon Dioxide (CO2) • In one test tube put 10 ml of water and 4 drops of bromothymol blue solution • Bromothymol turns yellow or green in the presence of CO2 • One person will take a straw and place it in the test tube. Another group member will act as a timer during this step. • SLOWLY blow air in the straw while being timed. • When the solution changes color, your partner should say “stop,” and then record how long the color change took.

  21. Activity • Procedure-Continued • Rinse out the test tube. • Refill with 10 ml of water and 4 drops of bromothymol blue. • The same person as before needs to jog in place for 1 minutes. • Repeat the procedure of blowing in the straw slowly and timing for color change. • Record how long the color change took.

  22. Activity • Answer the following questions in your lab notebook with the data you recorded. • How did exercise affect the time for the solution to change color? • What process in your body produces carbon dioxide? How does exercise affect this process?

  23. Fermentation • If oxygen is not present, glycolysis is followed by a different pathway • The combined process of this pathway and glycolysis is called FERMENTATION • Fermentation releases energy from food molecules in the absence of oxygen

  24. Fermentation • There are two types of fermentation • Alcoholic Fermentation • Lactic Acid Fermentation

  25. Alcoholic Fermentation • Produces carbon dioxide and ethyl alcohol as wastes • This is what is produced when yeast is used to make bread • When the yeast in the dough runs out of air, it begins to ferment and produces bubbles of carbon dioxide to rise the dough Pyruvic Acid + NADH = Alcohol + CO2 + NAD+

  26. Lactic Acid Fermentation • Produces lactic acid and NAD+ as wastes • Produced in your muscles during rapid exercise when the body cannot supply enough oxygen to the tissue Pyruvic Acid + NADH = Lactic acid and NAD+

  27. Quick Energy vs. Long Term Energy • The body provides enough ATP to last about 90 seconds-Quick Energy • Enough time for a runner to finish a 200-300 meter dash • Fermentation produces lactic acid as a by product • Getting rid of lactic acid requires oxygen • Thus a runner breathes heavily at the end of the race to rid the muscles of lactic acid that built up

  28. Quick Energy vs. Long Term Energy • How about when you need energy for a long time? • The body relies on cellular respiration to release energy more slowly • This is why athletes must pace themselves over a long race---why? • To allow oxygen to fuel the process of cellular respiration and make more ATP!!!

More Related