These are post lab questions regarding paper chromatography. Some background. The solvent used was a mix of HCl and acetone. We spotted the paper with 4 ions including Co(II), Cu(II), Fe(III), and Ni(II). After the solvent nearly reached the top, the paper was removed and measurements were made. Paper was dried and sprayed with ammonia. Changes observed and the paper was dried again and sprayed with sodium sulfide. Pleas help!

a)You used a pencil to mark the chromatography paper since the carbon in the pencil lead does not dissolve in the solute. Why does carbon not dissolve? What type of pen(ink) will also not produce a chromatogram when watert is used as the solvent? Explain using principles based on the polarity of particles.

b)You are to minimize hand contact with the paper since amino acids, oils, etc. on your skin will form a smudge on the cellulose paper. Why will using corroded tweezers also cause a smudge when sodium sulfide is sprayed on the paper?

c) What type of complexes appear when the spots are sprayed with Ammonia and why do new colors appear?

d) Same question as 'c' but being sprayed with sodium sulfide

The kinetics of chymotrypsin were studied and yielded a KM of 5 mM and a Vmax of 0.2 mM/min. The enzyme concentration was 0.20 μg/ml. Calculate the turnover number, assuming one binding site per enzyme.

1) When 10ug of an enzyme (MW 50,000) is added to a reaction mixture containing its substrate at a concentration one hundred times the Km, it catalyzes the conversion of 75umol of substrate into product in 3 min. What is the enzyme's turnover number?

2) You want to load 15g of protein in 10L into one of the 12% polyacrylamide gel well. The protein needs to be in 1X buffer and in a total volume of 0.100 ml. You are given a 4.5 mg/ml protein solution, a 20X sample buffer, and distilled water. How much of each would you mix together to make required volume?

3) The Km of an enzyme of an enzyme-catalyzed reaction is 6.5uM. What substrate concentration will be required to obtain 45% of Vmax for this enzyme?

Discuss the following enzymes: hexokinase, pyruvate dehydrogenase, ATP synthase and phosphofructokinase.

-How do these enzymes interact with their substrates and catalyze reactions?

-What is unique about each type of enzyme and why are each of the enzymes suited to the specific reactions which they catalyze including major points of regulation (enzyme catalysis, the mechanism of interaction of enzymes with their substrates and the effect of regulators/inhibitors on enzymes)?

-What is the organization of the active site for each enzyme? Are any of these enzymes considered cellular motors? Why?

50 units of protein A are required per cell to establish a wild-type phenotype. A single wild-type allele of gene A produces 40 units of enzyme per cell. Which of the following statements is true regarding the wild type allele. Select ALL that apply.

The AseI restriction enzyme recognizes the sequence ATTAAT. Which of the following prokaryotic genomes will on average yield thelargest fragments after cutting with this enzyme?

In general, if p is the number of predictor variables and k is the number of groups for the outcome variable in a DA, how many different discriminant functions can be obtained to differentiate among
groups? (This question assumes that the X predictor variables have a determinant that is nonzero; that is, no individual Xi predictor variable can be perfectly predicted from scores on one or more other X
predictor variables.)

Indicators are weak acids. Explain why we don’t see a buffer curve for them in the titration of the acids? What is it that makes methyl orange different from phenolphthalein (as an indicator)? How would one decide on an indicator to use for a given titration?