Biology lab, Rate of Cellular Respiration With and Without Exercise

  1. Rate of Cellular Respiration With and Without Exercise
  2. In this experiment, the process of cellular respiration will be examined through the production of CO2 gas. Since gases are invisible, CO2 production will be measured qualitatively by using a pH indicator called phenol red. Phenol red is orange in appearance with a neutral pH. Below a pH of 6.8, phenol red will turn yellow, and above a pH of 8.2, phenol red will turn bright pink. When CO2 dissolves in water, it forms a weak solution of carbonic acid. In an acidic solution, phenol red will turn yellow. In this part of the lab, changes in a phenol red solution will be examined to determine if CO2 is produced (as a byproduct of cellular respiration) by humans. Production of CO2 will be identified by a color change from orange or red to yellow.
  3. Place a test tube in the test tube rack.
  4. Using the 50 ml beaker, measure out 10 ml of tap water and then pour the water into the test tube.
  5. Place one phenol red tablet into the test tube containing the 10 ml of water. The water should turn orange or pink.
  6. Pick up the coffee stirrer and place it into the test tube with the phenol red solution. Using a stopwatch or timer, record how long it takes for the phenol red solution to turn yellow by blowing gently through the straw. Using a pen or pencil, record this time on a piece of paper.
  7. Pour the contents of the test tube down the sink and then rinse out the test tube with water.
  8. Repeat Steps B and C.
  9. Participate in 3 minutes of exercise. Either jog in place or complete jumping jacks for 3 minutes.
  10. Pick up the coffee stirrer and place it into the test tube with the phenol red solution. Using a stopwatch or timer, record how long it takes for the phenol red solution to turn yellow by blowing gently through the straw. Using a pen or pencil, record the time it took for the solution to turn yellow on a piece of paper.
  11. Pour the contents in the test tube down the sink and then rinse out the test tube with water. Place the test tube back into the test tube rack.
  12. Cellular Respiration in Peas
  13. Note: This section of the experiment requires a minimum of 4 hours to complete.
  14. In this experiment, pea seeds will be employed. Seeds are living but dormant. A seed consists of an embryo and a food supply that is surrounded by a protective coat. When the right conditions are present, the seed will germinate, causing an increase in cellular respiration. As discussed in the lab, all cells can transform energy through cellular respiration, including peas. In this part of the lab, peas will be utilized to examine the process of cellular respiration by observing the production of CO2 gas. Since gases are invisible, CO2 production will be measured qualitatively by using a pH indicator called phenol red. Phenol red is orange in appearance with a neutral pH. Below a pH of 6.8, phenol red will turn yellow, and above a pH of 8.2, phenol red will turn bright pink. When CO2 dissolves in water, it forms a weak solution of carbonic acid. In an acidic solution, phenol red will turn yellow. In this part of the lab, changes in a phenol red solution will be examined to determine if CO2 is produced (as a by-product of cellular respiration) which will be identified by a color change to yellow.
  15. Place several cups of tap water into a small pot and place the pot on the stove. Turn the stove on and heat the water until it boils. Once the water is boiling, remove 10 pea seeds from the bag found in the lab kit and place them into the boiling water. Turn down the heat on the stove so the water is at a slow boil and allow the seeds to boil for 10 minutes. After 10 minutes, turn the stove off and remove the pot from the heat. Using a spoon, remove the peas from the water and place them on a paper towel to cool.
  16. While waiting for the seeds to boil, place four test tubes into the test tube rack.
  17. Using a marker, label each test tube as follows:
    • Test tube 1: Control
    • Test tube 2: Dried peas
    • Test tube 3: Germinating peas
    • Test tube 4: Boiled peas
  18. Using the 50 ml beaker, measure out 10 ml of tap water and pour it into test tube 1. Repeat for test tubes 2 through 4. Each test tube should contain 10 ml of water.
  19. Place one phenol red tablet into each test tube.
  20. Tear a cotton ball in half and push it into test tube 1 until it is one-half inch above the phenol red solution. The cotton ball should not touch the phenol red solution.
  21. Repeat Step F for the remaining test tubes, placing half a cotton ball into each tube.
  22. Place the remaining 10 dried peas from the bag in the lab kit into test tube 2 so they rest on top of the cotton.
  23. Remove the 10 germinating seeds from the baggie or cup where you have been soaking them overnight and place them on a paper towel to drain. After they have drained, place the germinating peas into test tube 3.
  24. Place the 10 boiled peas into test tube 4.
  25. Place a black rubber test tube stopper into each of the test tubes. Make sure that the tube is sealed well with the rubber stopper.
  26. On a sheet of paper, create a table similar to the table below to record your results. Record the initial color of each test tube solution. Write down the starting time in the table under the column titled Initial (Time).
  27. Test Tube

    Color of Phenol Red Solution

    Initial

    (Time)

    After 1 hour

    (Time)

    After 2 hours

    (Time)

    After 3 hours

    (Time)

    After 4 hours

    (Time)

    1: Control

    2: Dried peas

    3: Germinating peas

    4: Boiled peas

  28. After 1 hour, record the time in the column titled After 1 hour. Observe the test tubes and record the color of each tube in the table.
  29. After results have been recorded for 4 total hours, dispose of the materials. Throw the peas and cotton in the garbage and pour the solutions down the sink. Rinse the test tubes with copious amounts of tap water and place them upside down on the test tube rack to dry. Retain all lab equipment for future use.
  30. Fermentation
  31. Stretch each balloon by blowing it up and then allowing the air to escape from the balloon.
  32. Using a permanent marker, label the balloons 1 through 6.
  33. Using a pencil or pen, create a table for your results similar to the one seen below.
  34. Balloon Circumference And Volume

    Balloon

    20 minutes

    (Time)

    40 minutes

    (Time)

    60 minutes

    (Time)

    120 minutes

    (Time)

    1: sugar

    C:

    V:

    C:

    V:

    C:

    V:

    C:

    V:

    2: sugar & salt

    C:

    V:

    C:

    V:

    C:

    V:

    C:

    V:

    3: sugar & lemon juice

    C:

    V:

    C:

    V:

    C:

    V:

    C:

    V:

    4: sugar substitute

    C:

    V:

    C:

    V:

    C:

    V:

    C:

    V:

    5: milk

    C:

    V:

    C:

    V:

    C:

    V:

    C:

    V:

    6: juice

    C:

    V:

    C:

    V:

    C:

    V:

    C:

    V:

  35. Place the tip of the funnel into the first balloon.
  36. Using the measuring spoon, add 1 teaspoon of yeast to the balloon by pouring it through the funnel and into the balloon. Repeat for each of the remaining five balloons adding 1 teaspoon of yeast to each balloon.
  37. Place the tip of the funnel back into the first balloon. Using the measuring spoon, add 1 teaspoon of sugar to the balloon by pouring it through the funnel and into the balloon. Repeat the procedure for balloons 2 and 3.
  38. Place the tip of the funnel back into the second balloon. Using the measuring spoon, add 1 teaspoon of salt to the balloon by pouring it through the funnel and into the balloon.
  39. Place the tip of the funnel back into the fourth balloon. Add the package of sugar substitute to the balloon by pouring it through the funnel and into the balloon.
  40. Using a cup, measure out 1 cup of very warm tap water. Check the temperature of the tap water with a thermometer: It should be between 105°F (40°C) and 115°F (46°C). If the water is too hot, it will kill the yeast, so be sure the temperature is within the specified range.
  41. Pour the warm water into the 50 ml beaker. Place the tip of the funnel into balloon 1 and slowly pour water into the balloon until it is full (it will probably take between 15 and 30 ml to fill the balloon).
  42. When the balloon is full, remove the funnel and then tie a knot in the balloon. Gently shake the balloon to mix the content.
  43. Repeat steps i, j, and k for balloons 2 and 4. Add more water to the 50 ml beaker, as needed.
  44. Repeat steps i and j; however only add 10 ml of warm water to balloons 3, 5, and 6. Do not tie the balloons at this time. Discard the remaining water.
  45. Using the 50 ml beaker, measure out 20 ml of lemon juice or vinegar. Place the tip of the funnel into balloon 3 and then add the lemon juice or vinegar to the balloon by pouring it through the funnel. When the balloon is full, remove the funnel and then tie a knot in the balloon. Gently shake the balloon to mix the contents. Discard the remaining lemon juice or vinegar and then rinse out the beaker with water.
  46. Using the 50 ml beaker, measure out 20 ml of milk. Place the tip of the funnel into balloon 5 and then add the milk to the balloon by pouring it through the funnel. When the balloon is full, remove the funnel and then tie a knot in the balloon. Gently shake the balloon to mix the contents. Discard the remaining milk and then rinse out the beaker with water.
  47. Using the 50 ml beaker, measure out 20 ml of juice. Place the tip of the funnel into balloon 6 and then add the juice to the balloon by pouring it through the funnel. When the balloon is full, remove the funnel and then tie a knot in the balloon. Gently shake the balloon to mix the contents. Discard the remaining juice and then rinse out the beaker with water.
  48. Record the start time once all of the balloons have been prepared. Place the balloons in a warm area and check on them after 20 minutes.
  49. After 20 minutes have elapsed, measure the circumference of each balloon and record the results in the table. To measure the circumference, place the length of string around the widest part of balloon 1. Pinch the string at the place where it meets the end of the string and then straighten the length of string alongside the metric ruler. Using the ruler, measure the length of string and record the data in cm (centimeters) in the table.
  50. Repeat step R for the remaining 5 balloons. Record the time.
  51. Repeat step R after another 20 minutes has elapsed (a total experiment time of 40 minutes).
  52. Repeat step R after another 20 minutes has elapsed (a total experiment time of 60 minutes).
  53. Repeat step R after a total experiment time of 120 minutes has elapsed.
  54. Calculate the volume of each balloon for each duration by using the formulas below.
  55. First, convert the circumference to a measurement called the radius by using the following formula.

    Radius (r) = Circumference (c)/6.28

    Then calculate the volume of each balloon by using the following formula.

    Volume (V) = 4.187 x (r)
    3

  56. Once all of the data have been entered into the table, discard the balloons and wash all equipment with plenty of running tap water.
  1. Define the following terms:
  2. Cellular respiration (aerobic respiration) (2 points)
  3. Fermentation (anaerobic respiration) (2 points)
  4. Summarize what occurs during the three steps of cellular respiration and indicate where each process takes place in the cell. (6 points)
  5. Glycolysis
  6. Krebs cycle
  7. Oxidative phosphorylation
  8. What is the primary energy molecule in cells? (5 points)
  9. List the equation in word and chemical form for each of the following processes: (6 points)
  10. Cellular respiration
  11. Alcoholic fermentation
  12. Lactic acid fermentation
  13. Does glycolysis require the presence of oxygen? Please explain your answer. (5 points)
  14. Review the results from the Rate of Cellular Respiration and Exercise procedure of the lab (Part I) to answer the following questions.
  15. Why was phenol red used as an indicator of cellular respiration? (5 points)
  16. How did exercise affect the rate of cellular respiration? (Hint: Review the time it took for the solution to change with and without exercise). (5 points)
  17. Review the results from the Cellular Respiration in Peas procedure of the lab (Part II) to answer the following questions.
  18. What color was the phenol red solution for each tube after 4 hours elapsed? (8 points)
  19. Control
  20. Dried peas
  21. Germinating peas
  22. Boiled peas
  23. Compare cellular respiration in the dried, germinating, and boiled peas. Explain why some peas in the experiment produced carbon dioxide (CO2) while other peas did not. (5 points)
  24. What is the advantage of cellular respiration? (5 points)
  25. Review the results from the Fermentation procedure of the lab (Part III) to answer the following questions.
  26. The balloons were sealed in this procedure. What is the name for the energy conversion process that occurs in the absence of oxygen? (2 points)
  27. What is the advantage of this process? (2 points)
  28. What type of gas is produced by yeast under anaerobic conditions? (2 points)
  29. What was the final volume of each balloon after 120 minutes? (6 points)
  • Based on the results, what was the best source of energy (e.g., food) for the yeast? (3 points)
  • Based on the results, what was the worst source of energy (e.g., food) for the yeast? (3 points)
  • What factors (ingredients) negatively affected the growth of yeast? (3 points)
  • What is the name for the type of fermentation that yeast use? (3 points)
  • List two commercial uses of fermentation. (2 points)
  • How might the information gained from this lab pertaining to cellular respiration and fermentation be useful to you in your everyday life or to a healthcare professional? (20 points)

    Biology lab, Rate of Cellular Respiration With and Without Exercise
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