1. (7pt) The Scholastic Aptitude Test (SAT) contains three sections: critical reading, mathematics and writing. Each part is scored on a 500-point scale. Information on test scores for the 2018 version of SAT is available at the College Board website. A sample of SAT scores for 5 students follow:

                                                                                                                       ANOVA Table

                 SAT scores - 2017

1. (5pt) Conduct a Fisher’s LSD test allowing for 5% error.

2. (2pt) The level of difficulty for all the three sections of the SAT, measured by the score, are supposed to be the same. Do you agree with this after the results of the LSD test? WHY?

1. Joshua used gel filtration chromatography to purify protein Z from crude homogenate prepared from Arabidopsis plants. He noticed that protein Z appeared to have eluted from the column in two separate peaks. Using a standard curve, he calculated the MW of protein Z eluted in the first peak to be 156 KDa, and the protein Z eluted in the second peak had the apparent MW of 78 KDa. Which one do you think is the correct MW? What does this tell you about the structure of the protein?

2. Read the following paragraph and correct all errors (4.15 points).

An unemployed high school student, Summer, has isolated a protein from a juniper tree with an overall negative charge. He performs ion exchange chromatography using a cationic resin with blue dextran to aid the proteins association with the column. As the proteins come off the column, the spec shows 4 peaks, only the first peak (wash peak) shows activity in an enzyme assay. Since all fractions associated with this peak had activity, they were pooled and total protein assayed. Total protein analysis was assayed using Bicine reagent which interacts with proteins to cause a change in absorption when measured with a spectrophotometer. The results of the total protein calculation showed that there was a modest decrease in total protein which means that there was a large amount of pure protein of his interest present in the sample.

3.You have accidentally mixed a bunch of amino acids (tryptophan, tyrosine, alanine, selenocysteine, proline, arginine) together and once your boss finds out, you will be fired on the spot. Your only hope of saving your job is to separate them before anyone finds out. You decide that the only viable option is to use ion exchange chromatography. Explain, in detail, how you would do this? (4.15 points)

4. Why should you not lose any LDH in your 20k x g spin? How does this explain an increase the fold purification of LDH in your 20k x g sample compared to your crude homogenate? (2 points)

Strong acids and bases completely dissociate in water. classify the following chemical compounds as strong acids, weak acids, strong bases, and weak bases.

1. H2SO4

2. KOH

3. HI

4. HCN

5. H2S

6. KF

7. Be(OH)2

8. NH3

Silver ions are known to react with the sulfhydryl groups of proteins and therefore and inhibit the action of certain enzymes. In one reaction, 0.0075 g of AgNO3 is needed to completely inactivate a 5-mL enzyme solution. Estimate the molar mass of the enzyme. Explain why the molar mass obtained represents the minimum value. The concentration of the enzyme solution is such that 1 mL of the solution contains 75 mg of the enzyme. Assume there is a 1:1 binding between silver ions and the protein.

For the simple enzyme model E + A<---> EA<---> E + P (with rate constants k1, k2, k3) Derive the expressions for the fraction of the total enzyme present as the free enzyme and for the fraction of the total enzyme present as the EA complex (simply the expressions to ensure they only contain A and Km as terms). Plot (E)/Et and (EA)/Et as a function of (A)/Km. Vary (A)/Km = 0.1 to 10 over about 10 concentrations. Say in a few words what this plot tells you

1. What is an enzyme?

2. How does an enzyme work? how does an enzyme, such as amylase, break down polysaccharides?

3. how does this compare to your mechanism by which saccharides break down in the stomach? Explain.

4. Do all sugars produce glucose when they break down?

5. Why is mother's milk lactose instead of maltose? What might be the difference between the two?

-A typed answer would be best, if not, please neat handwriting, thanks! :)

7) Canavan disease is a gene-linked neurological disorder, in which the brain degenerates into spongy tissues riddled with microscopic fluid-filled spaces. Canavan disease has been classified as a group of genetic disorders termed leukodystrophies. In the normal population, oligodendrocytes carry out an essential developmental task by producing myelin sheets, which constitute the fatty coverings that act as insulators around nerve fibers in the brain and provide nutritional support for nerve cells. In patients with Canavan disease, many oligodendrocytes do not mature and instead die, leaving nerve cell projections known as axons vulnerable and unable to properly function.

According to a group of investigators, Canavan disease is caused by a mutation in the gene that encodes for an enzyme called aspartoacylase, which breaks down the amino acid N-acetyl-aspartate. However, a competing laboratory published an article claiming that aspartoacylase mutation is not relevant for the pathogenesis and progression of Canavan disease.

Design an experimental plan to determine who is right. Include all the controls for full credit. Animal models cannot be used

2 In which property of protein, amino acid sides chains?

a) size

b) peptide bonding

c) function

d) donding

2 Wich of this statements its true about protein structure ?

a)Tertiary structure increases protein function, and quaternary structure decreases protein function.

b)Tertiary structure involves three basic forms of protein folding, and quaternary structure involves 4 basic forms of protein folding.

c) Tertiary structure involves all types of bonds (covalent, ionic, hydrogen, and hydrophobic interactions), and quaternary structure involves just hydrogen bonds.

d) Tertiary structure involves the folding of a single polypeptide, and quaternary structure involves the interaction of multiple polypeptides.

3) What process occur when a Ca+ ionbind to protein and this change the protein's dimensional shape?

A) enzyme activation

B) allosteric modulation

C) signal transduction

D) covalent modulation

4 Which molecule release more free energy when its oxidized?

a) fatty acid

b) polypeptide

c)benzonic acid

d)starch molecule