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# UB BIO 201LLB - Lab5_txt

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Table 1: Enter your measurements from Part 2 of the lab. Make sure to use the correct formula and cell references for the conversion factors!Table 1: Calibrating the ocular micrometerMeasurements Objective10x 40xmeasurement on stage micrometer (µm) 100.00 100.00ocular micrometer units (OMU) 10.00 40.00"Conversion factor (µm per micrometer unit; e.g. ""=E9/E10)"""10.00 2.50Table 2: Enter your measurements in ocular units; calculate the mean measurementfor each using Excel's 'Average' formula; calculate the standard deviations in ocular units using the Stdev formula; and convert the mean length and standard deviations from ocular units to µm using the appropriate conversion factors in Table 1. Remember to use cell references and formulas!!!. Do NOT enter numericalvalues directly. OMU = ocular micrometer unitsTable 2: ElodeaObjective Cell length (in OMU) Mean length (OMU) Standard deviation length (OMU) Mean length (µm)* Standard deviation length (µm)***For mean diameter in µm, use formula =Cell1*Cell2 where Cell1 is cell containing MEAN LENGTH IN OCULAR UNITS and Cell2 is the cell containing the APPROPRIATE CONVERSION FACTOR (i.e. cell E11 or F11 for 10x or 40x, respectively)1 2 310x 10.0 12.0 13.0 11.7 1.5 116.7 15.3 **For standard deviation in µm, enter formula =Cell1*Cell2 where Cell1 is cell containing standard deviation in ocular units and Cell2 is the cell containing the appropriate conversion factor.40x 21.0 23.0 29.0 24.3 4.2 60.8 10.4Objective Chloroplast length (in OMU) Mean length (OMU) Standard deviation length (OMU) Mean length (µm)* Standard deviation length (µm)**1 2 340x 0.9 1.0 1.0 1.0 0.1 2.4 0.1 * and ** See notes aboveNumber of your unknown 89Identity of your unknown* hypotonic(hypertonic/hypotonic/isotonic)*based on your observationsQuestions: Answer all questions below in the spaces provided.1. Compare the 10x and 40x measurements for Elodea cell length. Make sure you are comparing the averages in µm for the two objectives. How similar are the measurements?Elodea cell length: 10x has an average cell length of 116.7 um s, and 40x - 60.8 um. The differences between the two numbers are quite large. Thus, this leads to the fact that there were errors during the procedure.0.25 pts2. Assuming that at least some of the measuremens differ, which should you trustmore (10x or 40x) and why?I would trust more 40x because it gives the image of the Elodea cell bigger and cleaner. The measurements from 40x is more accurate since 40x is high power. 0.25 pts"3. Compounds that are not membrane permeable cause osmosis as we saw in this lab. Compounds that ARE membrane permeable themselves diffuse through the membrane and, therefore, do not cause osmosis. Formulate a hypothesis to addresswhether a newly-discovered compound is membrane permeable. In your hypothesis, make up a name for your compound. Remember that your hypothesis must be testable, e.g. using osmosis! Be specific: Your compound must have a name, and you must state what system you are going to test it on (it can't just be ""cells"")"Hypothesis: The effect of temperature on the permeable membrane of onion cells.0.25 ptsIndependent variable: different temperature.0.25 ptsDependent variable: the permeable membrane of onion cells.0.25 pts Negative control: room temperature.0.25 ptsTable 1 including formulas and cell references (1 pt):Table 2, incl. correct formulas, cell refs for means and std devs (0.5 pts):Table 2, Conversion to OMU using formulas and cell references (0.75 pts):Identification of unknown (0.25 pt):Total for Questions (1.5 pts):TOTAL PTS (4 possible):

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