a TiW layer is deposited on a substrate using a sputtering tool. the following table presents data, in Angstroms, from 20 subgroups of n=4. (a) Plot an x-bar and R control chart for the process. Perform run tests to western Electric rules 1 thru 5. Is the Process in Control? Revise the control limits as necessary. (b) Estimate the mean and standard deviation of the revised process. (c) Is the layer thickness of the revised process normally distributed? (d) if the specifications are 450 + - 30 Angstroms, estimate the process capability.  

Subgroup x1 x2 x3 x4

1 459 449 435 450

2 443 440 442 442

3 457 444 449 444

4 469 463 453 438

5 443 457 445 454

6 444 456 456 457

7 445 449 450 445

8 446 455 449 452

9 444 452 457 440

10 432 463 463 443

11 445 452 453 438

12 456 457 436 457

13 459 445 441 447

14 441 465 438 450

15 460 453 457 438

16 453 444 451 435

17 451 460 450 457

18 422 431 437 429

19 444 446 448 467

20 450 450 454 454

Theory of enzymes. [Indicate whether the following statements are true or false by writing T or F in the spaces provided.] _____ Enzymes catalyze reactions by increasing the reaction free energy (ΔG). _____ Enzyme are remarkable for their substrate specificity. _____ Enzyme can convert light energy into chemical or mechanical energy. _____ Catalytic residues in enzymes can include amino acid side chains, RNA bases, and other organic cofactors. _____ Michaelis-Menten kinetic theory only applies to enzymes with single substrates. _____ Enzymes bind transition-state analogs more tightly than substrates. _____ At high substrate concentration, reactions are rate-limited by how rapidly enzymes convert substrates into products. _____ KM = KD when kcat >> k-1 _____ kcat / KM is equivalent to a second-order rate constant. _____ Enzymes can use electrostatics to exceed the rate of diffusion (bimolecular collision of substrate with enzyme’s active site). _____ Drugs that bind to an allosteric site on an enzyme cause a decrease in kcat

What compound will you need to use to visualize the amino acids on thin layer chromatogram?

A student seperates a mixture of octane and 1-octanol using thin layer chromotography. Which compound will move faster with tolunce. Give reason.

You are a chemist working in a lab who is analyzing polar samples with thin layer chromatography. What type of solvent do you think would be ideal for your tests? Why?

α-helices and β-sheets are two types of secondary structure found in polypeptides.

a. What phi and psi angles describe the amino acids in a helix and sheet respectively?

b. Draw a representative diagrams, with appropriate labeling, to illustrate a helix and a sheet. On your diagram label the hydrogen bonds that are responsible for providing stability to these structures. You must illustrate your bonds using the appropriate H-bond donor and H-bond acceptor.

a. Outline the steps of the ribosome cycle. At what stage do the ribosomal subunits bind to each other? To mRNA? What causes them to dissociate when protein synthesis is complete? In detail.

b. Outline the steps by which aminoacyl tRNA synthetases charge tRNAs. How can some organisms get away with having fewer than 20 synthetases, yet still charge tRNAs with all 20 amino acids? In detail.

1. Outline the steps of the ribosome cycle. At what stage do the ribosomal subunits bind to each other? To mRNA? What causes them to dissociate when protein synthesis is complete?

2. Outline the steps by which aminoacyl tRNA synthetases charge tRNAs. How can some organisms get away with having fewer than 20 synthetases, yet still charge tRNAs with all 20 amino acids?

1. It is possible to convert the cysteine (Cys) that is a part of Cys-tRNACys to alanine (Ala) by a catalytic reduction. If the resulting Ala-tRNACys were added to a mixture of ribosomes along with tRNAs correctly charged with the other 19 amino acids, all the other cofactors and proteins needed to make proteins in vitro, and mRNA for Insulin, what effect on the primary structure, tertiary structure and function of the insulin thus made would you expect?

Describe the evidence for the fact that DNA is the genetic material and the sequence of events leading from the sequence of nucleotides of DNA to the sequence of amino acids in proteins and their secretion. Include in your answer:

a. the early evidence for the location of genes on chromosomes, the first evidence that DNA was the genetic material, and that genes determined the structure of proteins

b. a description of the mechanisms and structures involved in of transcription and translation c. a description of the cellular structures involved in protein synthesis and secretion

2. Describe the mechanism of targeting of proteins to the secretory pathway. Be sure to provide the step-by-step molecular mechanism of entry of proteins into the ER.

3. Outline an experimental progression involving site-directed mutagenesis to test the hypothesis that basic (positive) amino acids are important for opening a voltage gated ion channel.

Part 2 1. Discuss the difference between a genomic and cDNA library. Give details with respect to the preparation techniques.