Question

1. Look at the following data tables obtained by students who performed the experiment in the past and complete the following tasks:

1. Using table 1 as your data set, build your Standard Curve by plotting protein concentration in the x-axis and absorbance in the y-axis. Also ask Excel to include the data trendline, the R2 value and the equation for the linear regression. Don’t forget to label your axis.

2. Using the data provided by table 2 and the equation obtained from your standard curve, please calculate protein concentration in the undiluted Mitochondria and Wheat germ extracts. Hint: You can only work with absorbance values that “fit” within your standard curve. Hint 2: Remember to multiply by dilution factor if necessary.

Table 1. Standard Curve

Tube N	Protein (µg/tube)	A595
Blank	0	0.001
1	10	0.061
2	20	0.149
3	30	0.155
4	40	0.217
5	50	0.236

Table 2. Absorbance of different samples

		ABS
Mitochondria extract	Pure extract	0.217
	1/10 dilution	0
	1/100 dilution	0
	1/1000 dilution	0
Wheat Germ extract	Pure extract	2.26
	1/10 dilution	0.365
	1/100 dilution	0.159
	1/1000 dilution	0

Answer 1

Plot the below data point on excel sheet by selecting a scattered plot and then add trendline to get equation for linear regression and R² value and then label the X-axis as protein concentration and Absorbance at 595 nm.

Protein (μg/tube)	A595
0	0.001
10	0.061
20	0.149
30	0.155
40	0.217
50	0.236

For calculating protein concentration in undiluted mitochondria extract,

A₅₉₅ = 0.217 ( it is in range of standard curve)

Standard equation: y= 0.0047+ 0.0187x

So, x = (y - 0.0187)/ 0.0047

x= (0.217 - 0.0187)/0.0047 = 42.1914 µg/tube

For calculating protein concentration in undiluted wheta germ extract,

Given, A₅₉₅ = 0.159 ( for 1:100 dilution which is in range of standard curve)

Standard equation: y= 0.0047+ 0.0187x

So, x = (y - 0.0187)/ 0.0047

x= (0.159 - 0.0187)/0.0047 = 29.85106

So, final concentration of undiluted wheat germ extract = (x * dilution factor) = 29.85106 *100 = 2985.106 µg/tube