December 8, 2011
AP Biology Lab 5: Cellular Respiration
In this lab we are testing how the process of cellular respiration is affected by temperature, and also how it is different between germinating and non-germinating peas. Cellular respiration is a catabolic process (breaks down organic material into usable cell energy) that produces ATP. The electron receivers are inorganic. Cellular respiration releases energy from organic material through chemical oxidation within the mitochondria of cells. Cellular respiration usually refers to the metabolizing of glucose, however carbohydrates, proteins and fats can also be metabolized.
C6H12O6 + 6O2 → 6CO2 + 6H2O + 686 Kcal of energy/mole of glucose oxidized …show more content…
|Corr. Diff. |Reading |Diff. |Corr. Diff |Reading |Diff. | |18 |0 |.80 |- |- |1.10 |- |- |.65 |0 | |18 |5 |1.45 |-.65 |-.65 |1.10 |0 |.05 |.70 |-.05 | |18 |10 |1.75 |-.95 |-.90 |1.10 |0 |.05 |.70 |-.05 | | |15 | | | | | | | | | | |20 | | | | | | | | | | |25 | | | | | | | | | | |30 | | | | | | | | | |Vials 4-6
8 |0 |1.65 |- |- |1.05 |- |- |.90 |- | |9 |5 |1.65 |0 |.1 |.8 |.25 |.35 |1 |-.10 | |9 |10 |1.25 |.4 |.4 |.5 |.55 |.55 |.90 |0 | | |15 | | | | | | | | | | |20 | | | | | | | | | | |25 | | | | | | | | | | |30 | | | | | | | | | | | | | | | | | | | | |[pic]
In this lab the vials with beads only serve as a control, because the beads do not go through cellular respiration. With the data from vials 1-3 we can see that the dye travelled the most in the respirometer with germinating peas, this is because in cellular respiration germinating peas require the most oxygen to survive and grow. The dye is travelling because as the oxygen is being consumed by the peas, the oxygen is being taken out and the pressure within the respirometer decreases; pulling the dye towards the respirometer. While non-germinating peas are also alive, they currently require much less oxygen to survive. In vials 4-6 from what I see looking at the non-germinating peas, the readings are smaller, meaning in a cold temperature …show more content…
We can also see the differences in cellular respiration between germinating and non-germinating peas. In our lab the main error made was that I accidentally bumped the chilled water tray, moving the respirometers equilibrating inside the tray, therefore resulting in botched results.
CELLULAR RESPIRATION ASSESSMENT QUESTIONS 1. The rate of oxygen consumed by germinating peas increases over time (at least in 1 of out data sets), meaning that they require a lot of oxygen to survive. 2. Three controls used in this lab are the temperatures of the water baths, the amount of KOH added to the vials, and the time intervals in which we recorded rates of oxygen consumption. 3. The water initially moved into the respirometer because we had to fully submerge the respirometer. I don’t think we could have avoided some water getting inside the graduated pipet. 4. The role of KOH is to prevent the release of CO2, but K2CO3 we see at the bottom of the respirometers. Without CO2, we can accurately measure how much oxygen is being used without the release of CO2 effecting those readings. 5. The KOH absorbs the CO2, therefore affecting the volumes within the