Working with Proteins for the Study of a Protein in Detail,an
Working with proteins For the study of a protein in detail,an effort is usually made to first:
A)conjugate the protein to a known molecule.
B)determine its amino acid composition.
C)determine its amino acid sequence.
D)determine its molecular weight.
E)purify the protein.
Working with proteins In a mixture of the five proteins listed below,which should elute second in size-exclusion (gel- filtration)chromatography?
A)cytochrome c Mr = 13,000
B)immunoglobulin G Mr = 145,000
C)ribonuclease A Mr = 13,700
D)RNA polymerase Mr = 450,000
E)serum albumin Mr = 68,500
Working with proteins By adding SDS (sodium dodecyl sulfate)during the electrophoresis of proteins,it is possible to:
A)determine a protein's isoelectric point.
B)determine an enzyme's specific activity.
C)determine the amino acid composition of the protein.
D)preserve a protein's native structure and biological activity.
E)separate proteins exclusively on the basis of molecular weight.
Working with proteins To determine the isoelectric point of a protein,first establish that a gel:
A)contains a denaturing detergent that can distribute uniform negative charges over the protein's surface.
B)exhibits a stable pH gradient when ampholytes become distributed in an electric field.
C)is washed with an antibody specific to the protein of interest.
D)neutralizes all ionic groups on a protein by titrating them with strong bases.
E)relates the unknown protein to a series of protein markers with known molecular weights,Mr.