Question

Absorbance Values for Physiology-Effect of pH The absorbance values for the haloarchaeans grown at pH values are given below. The pH range used in this experiment is 3 - 9. Turbidity was measured at 600 nm using a spectrophotometer. This part of the experiment was run a total of six times. Present the average absorbance values and show the +/- y-axis standard deviation bars in your presentation. Halobacterium salinarum pH Absorbance Absorbance Absorbance Absorbance Absorbance Absorbance Trial 1 Trial 2 Trial 3 Trial 4 Trial 5 Trial 6 0.000 0.000 0.000 0.000 0.001 0.005 0.000 0.000 0.000 0.000 0.002 0.010 0.125 0.099 0.135 0.165 0.170 0.128 0.427 0.587 0.521 0.597 0.503 0.420 7 0.879 0.963 1.010 0.924 0.857 0.900 8 0.713 0.602 0.668 0.497 0.563 0.644 0.100 0.079 0.065 0.052 0.033 0.081 Raaditaan

Answer 1

From the above data as provided in the table, we can first calculate the average value of all readings at different pH Values.

Average value can be calculated as: Sum of all the readings at particular pH/ No. of readings

pH	Average absorbance	Standard deviation
3	0.000+0.000+0.000+0.000+0.001+0.0005/6 = 0.006/6 = 0.001	0.0000033
4	0.006	0.000005
5	0.137	0.0266
6	0.509	0.0757
7	0.922	0.0565
8	0.614	0.0135
9	0.068	0.0236

Standard deviation can be calculated as

The graph with error bars will be