Experimental Background

Bovine Serum Albumin (BSA) is a protein that circulates in the blood of cows. Purified BSA can be used with Biuret solution in serial dilutions to generate a Standard Curve. The standard curve will illustrate the relationship between concentration (the dependent variable) and absorbance at 540 nm (the independent variable).  We can then use this curve to estimate the concentration of unknown samples.

1. On a graph, do you remember which axis is the dependent and which is the independent variable?
2. In the table below, can you identify which samples are the negative controls and which are the positive controls?
3. What is the prediction of the absorbance or color intensity of the different tubes?