Question

EFFECT OF WATER-SOLUBLE POLLUTANTS ON MEMBRANE PERMEABILITY Treatment Group Treatment Solution (% by volume) 70% isopropanol; 30% water 90% isopropanol; 10% water 50% acetone; 50% water 70% acetone; 30% water 100% water Mean Absorbance of 460 nm Light (n = 5) 0.164 0.125 0.215 0.274 0.095 2xStandard Error of the Mean (2xSEM) 0.032 0.100 0.034 0.018 0.004 A student formulated a hypothesis that water-soluble pollutants damage living organisms by increasing the permeability of cellular membranes. To test the hypothesis, the student investigated the effects of isopropanol and acetone on beet root cells. The student prepared identical samples of beet root tissue and incubated each sample for 15 minutes in the specific solution for that group. At the end of the incubation period, the student measured the absorbance of 460 nm light for each sample. Greater tissue damage by Increased membrane permeability results in a greater absorbance of 460 nm light. The results of the experiment are shown in the table above. Which of the following best summarizes the null hypothesis? A. If more isopropanol is added to beetroot cells, the absorbance of 460 nm light will be greater. OB. Acetone causes more damage to beet root cells than isopropanol does. OC. Treatment group V will have the lowest standard error of the mean. D. Beetroot cells in all treatment groups will have a similar mean absorbance of 460 nm light.

Answer 1

The best summerizes the null hypothesis is

Answer(A)-If more isopropanol is added to beet rootcells,the absorbance of 460 nm light will be greater.