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A student was assigned the task of estimating the protein concentration in a sample of milk. They first prepared a standard protein curve (see below) using varying concentrations of bovine serum albumin (BSA) and the colorimetric Bradford dye assay. The absorbance of the blue protein complex which forms is measurable spectrophotometrically at 595 nm ( ${ Abs }_{ 595 }$).

M. Rumpho-Kennedy. Created for Albert.io. Copyright 2016. All rights reserved.

The student first diluted the 100-mL milk sample 10-fold and then assayed 2 different volumes using the standard assay and assembled the following data:

Diluted Milk Volume (${ \mu L }$) ${ Abs }_{ 595 }$
5 0.005
100 0.50

Which of the following statements is UNTRUE concerning the analysis of this data set?

A

The protein concentration cannot be accurately estimated using the 5${ \mu L }$ sample, but the 100 ${ \mu L }$ sample yields an accurate estimation of 400 ${ \mu g }$ total protein in the 100-mL sample.

B

The protein concentration cannot be accurately estimated using the 5${ \mu L }$ sample because the measured absorbance (0.005) is below the readable level of the standard curve.

C

The protein concentration cannot be accurately estimated using the 100 ${ \mu L }$ sample because the measured absorbance (0.50) is above the linear range of the standard curve.

D

The protein concentration of the 100 ${ \mu L }$ sample will likely be under-estimated using the measured absorbance (0.50) value and this standard curve.

E

The protein concentration of the milk cannot be accurately determined using either of the 2 measurements.

Accuracy 0%
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