Effects of Persistent and Bioactive Organic Pollutants on Human Health - Lab Report Example

Cellular Respiration and How Pollutants Affect Its Rate This experiment seeks to show how significant cellular respiration is in real life processes. We were also attempting to explore the effect of change in carbohydrate supply on the rate of cellular respiration. We verified if pollutants harm life by disrupting the organisms’ capability to accomplish cellular respiration. The experiment scrutinized how cellular respiration functions in smaller organisms with yeast. To explore how carbohydrates impact cellular respiration, we introduced sugar to the yeast. We also added various pollutants to the yeast while measuring the level of carbon dioxide to ascertain how the pollutant impacted the cellular respiration rate. The amount of gas emitted at the top of tube was observed to over 10 minutes so as to determine cellular respiration rate. The pollutants used included; vinegar, salt solution, isopropyl alcohol, baking soda, soap solution, and bleach solution. The result for yeast mixture was compared with the results for yeast-sugar mixture. The yeast-sugar mixture exhibited a faster cellular respiration rate. The outcomes of the pollutants had mixed results. Except baking soda, most of the pollutants utilized had a lower cellular respiration rate. Introduction According to Carpenter (2013), cellular respiration is a process in which chemical energy in the food is reaped and converted into energy that is utilized in carrying out the normal life process. Every organism requires cellular respiration for survival. This process happens in three distinct phases; glycolysis, Krebs cycle, and electron transport chain. Lippmann (2009) argues that during these cycles, oxygen and glucose in our body are turned into carbon dioxide, energy, and water. The first phase of cellular respiration is when one glucose molecule is split to produce two pyruvic acid molecules, a 3-carbon compound (Schapira, McQuaid & Froneman, 2011). This first phase is anaerobic, implying it does not need oxygen to occur. The remaining phases require oxygen. As such, the experiment was conducted within an oxygen zone and a considerable time frame to allow the three phases of cellular respiration to occur. The objectives of our experiment were; i. To discover how cellular respiration rate is affected by carbohydrates ii. To ascertain if cellular respiration rate is affected by pollutants. As such, we developed the following hypotheses; a) An organism will experience a larger cellular respiration rate in the presence of carbohydrate than when there is no source of carbohydrate. b) An organism will experience a lower cellular respiration rate in the presence of carbohydrate and a pollutant compare to in the presence of carbohydrate but no pollutant. To test our first hypothesis, the experimental design was such that yeast was mixed with water then poured into a test tube. A wider test tube was placed over the yeast test tube and flipped together over 10 minutes to observe the level of gas amounting in the wider tube. The amount of gas was recorded every minute in the10 minutes. The same was done to a yeast-water mixture but with granulated sugar added into the mixture. To test our second hypothesis, another mixture of yeast and carbohydrate was created and the pollutant assigned to each group added into the mixture this time. A similar procedure was redone as illustrated above. Methods We took a marker and labeled the two 15mL centrifuge tubes, two 25mL x 250mL test tubes, and the two 50 mL beakers. Y denoted yeast, W denoted water, and S denoted sugar. The tubes were placed into test tube rack and 150mL of hot water poured into the 250mL beaker. 2.5mL of yeast was then poured into beaker 1 while 2.5mL of crushed sugar and 2.25mL of yeast poured both into the second beaker.13mL of warm water was added into each beaker and swirled thoroughly to mix the content in each beaker. We poured the solution of beaker 1 into test tube1 and inverted test tube 1 and placed it over centrifuge tube 1. We used a finger of one hand to push the centrifuge tube 1 up into the inverted test tube 1, held it in that position while holding test tube 1 with the other hand. We then quickly invert test tube1 back into normal upright position with one had while applying pressure to centrifuge 1 against the bottom of test tube 1. With this, we found the initial gas volume in centrifuge tube 1 and record the value for time=0. Tube1 and centrifuge tube1 were placed into the 250mL beaker with hot water to speed up the reaction time. We repeated the same steps for beaker 2, centrifuge tube 2 and test tube 2. The volume of gas in each centrifuge tube in every 1 minute over a span of 10 minutes were found and recorded. We cleaned up the lab by pouring all the solutions and water down the sink and washed each beaker and test tube properly. Again, we placed 150mL of hot water into the 250mL beaker and took 2.5mL of yeast and 2.5mL of crushed sugar and poured both into the 25mL beaker. We added 10mL of warm water into the 250mL beaker and swirled each beaker to mix them together. We finally added 3mL of the simulated pollutant which was assigned to our group and repeated the same process as before. Results The volume of CO2 in mL at an interval of 1 minute for 10 minutes was taken for centrifuge tube containing water and yeast and for water, yeast, and sugar. Table A. show the results. Table A. Amount of gas over 10 min Tube No. Contents Gas volume (mL) in the Centrifuge Tube at Time t Minutes 0 1 2 3 4 5 6 7 8 9 10 1 Yeast + Water  1.8 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2 Yeast + Water + Sugar 4 5 5 7 9 11 14 15 17 19 21 Note: Y-axis represents the amount of carbon dioxide (ml), X-axis represents time in minutes The results displays that yeast with carbohydrate had a higher cellular respiration rate. Water and yeast solution only had 2.3ml carbon dioxide from the first minute to the end. The amount of CO2 in water, yeast, and sugar solution increased with time. The same was done with each of the six simulated pollutants added to the water, yeast, and sugar solution at a time. Table B. shows the outcomes. Table B. Amount of Carbon dioxide in 10 minutes Group No. Simulated Pollutant Gas Volume (mL) in the Centrifuge Tube at Time t 0 1 2 3 4 5 6 7 8 9 10 1 Isopropyl alcohol 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2 Bleach solution, 1% 4 4 4 4 4 4 4 4 4 4 4 3 Salt Solution, 10% 2.5 2.5 2.5 3 5 7 7.3 7.8 8.4 9 10 4 Soap solution, 10% 5 5.5 6 7 7.5 8.3 9 9.6 10 10.8 11 5 Baking Soda solution, 5% 0 1 2 4 5 14 19 21 21 21 21 6 Vinegar 4 4 6 3 3 3 3 3.6 3.9 3.5 2.8 Note: Y-axis represents the amount of carbon dioxide (ml), X-axis represents time in minutes The baking soda solution produced the highest amount of CO2 implying it increased cellular respiration rate the most. Isopropyl alcohol solution, bleach solution, and vinegar did not have much effect on cellular respiration rate. The amount of CO2 in salt solution started to increase after the 3rd minute. Discussion Our results confirmed hypothesis 1. The reason why this happened is because our yeast had a source of energy. In order to carry out cellular respiration the organism needs a source of energy and the organism used the granulated sugar as a source of energy. Since the yeast had a source of energy it could go through the processes of cellular respiration more than it could without having any source of energy (Schapira, McQuaid & Froneman, 2011). The hypothesis 2 was also supported by this experiment. The results had that the mixtures with the simulated pollutants all had a lower cellular respiration rate than a carbohydrate mixture with no pollutants. The reason why this happened is because most of pollutants used were harmful to living organisms. Most of the pollutants used in this experiment were harmful to the yeast disabling its ability to carry out cellular respiration. There was one pollutant that had actually increased the rate of cellular respiration, baking soda. The reason this happened is because baking soda has some molecules similar in carbohydrates such as hydrogen, carbon, and oxygen.   References Carpenter, D. O. (2013). Effects of persistent and bioactive organic pollutants on human health. Hoboken, New Jersey: Wiley. Lippmann, M. (2009). Environmental toxicants: Human exposures and their health effects. Hoboken, N.J: Wiley. Largen, K. B. (2010). Environmental science lab manual and notebook. (Vol. 1, pp. 111 117).Dubuque, IA: Kendall Hunt. Schapira, M., McQuaid, C. D., & Froneman, P. W. (2011). Metabolism of free-living and particle-associated prokaryotes: Consequences for carbon flux around a Southern Ocean archipelago. Journal of Marine Systems [J. Mar. Syst.]. Vol. 90, (1), 5866.doi:10.1016/j.jmarsys.2011.08.009 Read More