BI208 Practicals Flashcards
Precision
How close the values obtained are to each other / how reproducible the measurements are
Accuracy
How close the values obtained are to real/expected value
Random error
Measurements vary from the average, related to precision
Systematic error
Average value varies from true value, related to accuracy
Interpolation
Inferring a value from within the range of known points. Assume the trend line is a reasonable fit
Extrapolation
Inferring a value outside the range of known points. Assumes the trend line will continue
Assay
Procedure where an analyte property or concentration is measured
Analyte
Substance being investigated in an analytical procedure
Standard
Analyte of known properties or concentration to be compared with unknown
Biuret assay
The measuring of protein concentration based on interaction of Cu2+ with peptide bonds in an alkaline solution
Lowry assay
Extension of biuret assay by subsequent reaction with Mo6+/W6+
Standard curve
Plot of response range of assay standards to interpolate unknowns
Isoelectric point of proteins
pH at which protein has a neutral charge
7 ionisable sidechains
Tyr, Cys, Asp, Glu, Lys, Arg, His
How do we observe the effect of pH on casein solubility?
pI is pH at which casein is most insoluble (absorbable is highest)
