Midterm Review Flashcards
Which of the following factors or variables will NOT affect the Rf (retardation factor) values of solutes during the paper chromatography experiment?
A. solutes with different conformational isomers
B. paper type
C. solvent composition
D. all of the above
A. Solutes with different conformational isomers
Formula for percent error:
[Experimental - theoretical] / theoretical
\_\_\_\_\_ is used to quantify the accuracy of an experiment. A. percent error B. standard deviation C. regression coefficient D. best fit line
A. percent error
\_\_\_\_ is used to quantify precision of an experiment. A. percent error B. standard deviation C. regression coefficient D. best fit line
B. standard deviation
What portion of the amino acid structure determines the difference of polarity among different amino acids?
R-group
What is the most non-polar amino acid? A. Glycine B. Alanine C. Valine D. Leucine
A. Glycine
Under the same conditions as used in the paper chromatography lab which amino acid will have the most affinity for the stationary phase? A. Glycine B. Alanine C. Valine D. Leucine
C. Valine
\_\_\_\_\_\_ reagent was used to detect amino acids on the paper chromatogram. It reacts with \_\_\_\_ group of amino acids and gives purple colored product. A. Ninhydrin, hydrogen B. Bromophenol blue, R-group C. Ninhydrin, amino group D. Bromophenol blue, carboxyl
C. Ninhydrin, amino group
In gel filtration chromatography, the _____ (larger or smaller) proteins cannot enter the pores of the resin/matrix and thus elute _____ (earlier or later) from the column.
Larger; earlier
To elute target proteins from a gel filtration chromatography matrix, which of the following conditions would be the most appropriate?
A. change the pH of the elution buffer
B. gradually increase the salt concentration of the elution buffer
C. Adding soluble ligand to the elution buffer which competes with binding to the affinity tagged proteins to the column
D. Just keep adding the wash buffer through the column and start collecting samples
D. Just keep adding the wash buffer through the column and start collecting samples
To elute target proteins from an affinity chromatography column, which of the following conditions would be the most appropriate?
A. change the pH of the elution buffer
B. gradually increase the salt concentration of the elution buffer
C. Adding soluble ligand to the elution buffer which competes with binding to the affinity tagged proteins to the column
D. Just keep adding the wash buffer through the column and start collecting samples
C. Adding soluble ligand to the elution buffer which competes with binding to the affinity tagged proteins to the column
Which statement below about GFP and BFP is FALSE?
A. Researchers can now connect/tag GFP to other interesting, but otherwise invisible proteins. This glowing marker allows them to watch the movements, positions and interactions of the tagged protein
B. GFP occurs naturally in jelly fish, A. victoria, while BFP occurs naturally in blue fish.
C. Blue fluorescent protein is a derivative variant of the gfp. It has a His-66 substitution at the Tyr-66 position and a second substitution from Tyr-145 to Phe-145
D. A set of gfp and bfp proteins can be used as a dramatic tool to visually demonstrate the effect of pivotal amino acid changes on the structure and function of proteins
B. GFP occurs naturally in jelly fish, A. victoria, while BFP occurs naturally in blue fish.
Protein purification by affinity chromatography takes advantage of the ____ of the protein to be purified.
A. polarity
B. biological activity (affinity to ligand)
C. size
D. shape
B. biological activity (affinity to ligand)
In SDS-PAGE (gel electrophoresis), the denatured proteins are _____ (+ or - charged) because it binds to _____ (reagent) and moves towards the _____ electrode.
A. Neg, SDS, positive (anode)
B. Pos, glycerol, negative (cathode)
C. Neg, glycerol, positive (anode)
D. Pos, Coomassie Blue, negative (cathode)
A. Neg, SDS, positive (anode)
To determine the molecular mass of an unknown protein, you would use \_\_\_ form of the protein because it would overcome the \_\_\_ factor associated with its \_\_\_\_ form. A. denatured, shape, native B. denatured size, native C. native, shape, denatured D. native, size, denatured
A. denatured, shape, native