Lab Instructions_ Cell Biology Act I Mission Memo (Spring A 2024 Onward)

.pdf

School

Arizona State University *

*We aren’t endorsed by this school

Course

181

Subject

Biology

Date

Apr 27, 2024

Type

pdf

Pages

21

Uploaded by GeneralWorld11374 on coursehero.com

Lab Instructions: Cell Biology Act I Mission Memo Greetings Fellow Explorer: The spotted gliders in the Allurian Forest need your help! Many gliders have succumbed to a mysterious illness. Thanks to your careful analysis, we now have a probable diagnosis: cancer. Still, cancer doesn't usually affect a large fraction of a population. Therefore, we must learn what caused this widespread disease and decide how to treat it. Use the following questions to guide your work: Are elevated concentrations of carcinogens in water, air, or soil to blame for the widespread cases of cancer in spotted gliders? (Appendices 1 and 2) How could a malfunction in cellular communication have caused the cancer in spotted gliders? (Appendix 3) Universally in your debt, The AI
Note: You will be using the program Microsoft Excel for this assignment. We have provided links to Excel tutorials and transcripts where applicable, to help you answer the questions. Appendix 1 Could the widespread cases of cancer in spotted gliders be explained by elevated levels of carcinogens in the water? Cancer results from mutations in genes that cause cells to reproduce uncontrollably. Often, these mutations occur when certain chemicals from the environment—called carcinogens —interact with the genetic material in cells. At low concentrations, carcinogens present a low risk of cancer. However, an artificial environment such as the Intergalactic Wildlife Sanctuary could contain elevated levels of carcinogens. Some known carcinogens are found in the structural framework of the sanctuary. Therefore, the carcinogens could have accumulated in the water, air, or soil of the Allurian Forest. The Intergalactic Wildlife Federation (IWF) follows the health and safety recommendations of the Galactic Environmental Treaty, which limits the concentrations of potentially harmful chemicals. This treaty specifies that drinking water should contain less than 10 micrograms of a given carcinogen per liter (< 10 µg/L). Any concentration greater than this limit could increase the risk of cancer. Your water samples from the Allurian Forest are critical for determining whether a carcinogen could have caused the tumors in spotted gliders. Why? Since we don’t have data on the concentration of carcinogens in the tissues of sick and healthy spotted gliders, knowing the concentration of carcinogens in the water where the sick spotted gliders were found is the next best set of information to help us determine if elevated concentrations of carcinogens could be to blame for the widespread cases of cancer in spotted gliders. We will follow three steps to answer the question “Could the widespread cases of cancer in spotted gliders be explained by elevated levels of carcinogens in the water?”
Step 1: Anticipate your analysis : Determine what you should observe if the concentration of carcinogen in water exceeds the recommended limits. This step will help us identify the evidence needed to build an argument in Step 3. Step 2: Calculate the probability that the concentration of carcinogen in water exceeds the recommended limit of 10 µg/L: Determine whether the concentration of carcinogen in water likely exceeds the recommended limits. This step gives us the evidence needed to build an argument in Step 3, when we will conclude if an elevated concentration of carcinogens in the water could explain the widespread cases of cancer in spotted gliders. Step 3: Weigh the evidence and conclude if an elevated concentration of carcinogens in the water could explain the widespread cases of cancer in spotted gliders: Construct an argument to answer the question “Could the widespread cases of cancer in spotted gliders be explained by elevated levels of carcinogens in the water?” Your argument should draw on your calculations in Steps 1 and 2.
Step 1: Anticipate your analysis. To construct a sound argument, one must anticipate the evidence needed to support a claim. In this assignment, you can choose between two claims: Potential Claim 1: Yes, the widespread cases of cancer in spotted gliders could be explained by elevated levels of carcinogens in the water. Potential Claim 2: No, the widespread cases of cancer in spotted gliders could not be explained by elevated levels of carcinogens in the water. The figure below shows the mean concentration of carcinogen in the water at three different locations. In the figure, the y-axis represents the mean concentration of carcinogen, with higher values indicating more carcinogen. The x-axis represents the different locations where the water was tested for the carcinogen. The dashed line indicates the recommended limit of carcinogens, 10 µg/L (µ is the Greek letter “mu” and µg is the abbreviation for micrograms per liter [L] of water; µg/L). Finally, the solid circles represent the mean concentration of carcinogen in the water at each location. Figure 1.0. 1. Select the location that best illustrates what one should expect to observe if the concentration of carcinogen in water exceeds the recommended limit of 10 µg/L. a. Location A b. Location B c. Location C
Step 2: Calculate the probability that the concentration of carcinogen in water exceeds the recommended limit of 10 µg/L . Excel tutorials: #6 Functions: Describing Data ; #6 Functions: Describing Data transcript #7 Functions: The Count Family and Absolute Cell References ; #7 Functions: The Count Family and Absolute Cell References transcript #8 Calculating Frequencies ; #8 Calculating Frequencies transcript #10 Estimating Parameters of a Normal Probability Distribution ; #10 Estimating Parameters of a Normal Probability Distribution transcript #11 Calculating a Probability from a Normal Probability Distribution ; #11 Calculating a Probability from a Normal Probability Distribution transcript To determine if the widespread cases of cancer in spotted gliders could be explained by elevated levels of carcinogens in the water, we will need to determine whether the concentration of carcinogen in water exceeds the recommended limit. To do this, we must estimate the probability that the water contains a concentration of carcinogens greater than 10 µg/L. Before we can estimate that probability, we must determine whether a normal probability distribution reasonably describes the frequency distribution of carcinogen concentrations. If not, we should use the data to calculate the probability instead of using a normal probability distribution. Download the Excel file titled “Act I: A Mysterious Disease Workbook,” containing the concentrations of carcinogen in 20 water samples collected from the Allurian Forest. Then, decide whether the data can be modeled with a normal probability distribution. We need to be sure the data meet the assumptions of this model before using it to draw conclusions. Directions : For questions 2-4, download the “Act I: A Mysterious Disease Workbook” from your Canvas assignment and refer to the sheet titled “Question 2,” containing the concentrations of carcinogen in water samples from the Allurian Forest (sample size = 20 water samples). Use Excel for calculations, modeling, and graphing. Round all calculated values to the nearest tenth of a decimal place. For example, if you calculate the value as 3.8218, round to 3.8. 2. Use the sheet (tab) labeled “Question 2” to create a plot of a frequency distribution (also known as a histogram) of the concentration of carcinogen in water (sample size = 20 water samples). Your plot should follow the formatting guidelines listed below.
Hint: If you are having trouble with the cell formatting when entering the bin ranges in your spreadsheet, format only the bin range cells as “Text.” Excel tutorials: #8 Calculating Frequencies ; #8 Calculating Frequencies transcript #9 Saving Plots as Images ; #9 Saving Plots as Images transcript Formatting Instructions Chart type: 2D Bar Chart Chart title: “Frequency of Carcinogens in Water” Y-axis title: “Frequency”; Font size = 18 Y-axis numbers: Font size = 14 X-axis title: “Concentration of Carcinogen (µg/L)”; Font size = 18 X-axis numbers: Font size = 14 Bins = Use the following 6 bins: 0-1, 1-2, 2-3, 3-4, 4-5, 5-6 3. Based on the frequency distribution, does a normal probability distribution reasonably model the concentration of carcinogen in water? 4. Explain your answer to the previous question. Be sure to discuss the assumptions of a normal probability distribution and why, based on the frequency distribution, these assumptions seem appropriate (or not) for modeling the concentration of carcinogen in water. Now that we have determined whether the data can be reasonably modeled by a normal probability distribution, we can estimate the probability of observing a certain concentration of carcinogen in the water of the Allurian Forest. Your approach to estimating this probability should depend on whether the data can be reasonably modeled by a normal probability distribution. Let's compare two approaches, one that uses a normal probability distribution and one that uses only the data. Note: You will answer both approaches (questions 5 and 6), regardless of your answers to questions 3 and 4. Approach 1: Use the normal probability distribution to estimate the probability Let’s assume that a normal probability distribution reasonably describes the data. In this case, you should use the following approach to estimate the probability that the concentration of carcinogen in water exceeds the recommended limit of 10 µg/L: (1) Estimate the mean and standard deviation of the concentration of carcinogen. No the probability distribution doesn't have a symmetrical bell shaped curve + does not have evenly distributed tails . Off
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
  • Access to all documents
  • Unlimited textbook solutions
  • 24/7 expert homework help