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salmansiddiqui

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  1. I need to know if there is any training available? I have passed FPGEE and TOEFL ibt. I am struggling to get training. I have called every where in Houston Tx but no one seems to be interested hiring a trainee. Thanks in advance
  2. salmansiddiqui

    ibt news

    Alnik You sound very much stressed out..don't worry just have to concentrate and we can make it...if we can do FPGEE I am sure we will get through this TOEFL as well.
  3. My friend had a same problem and ETS did nothing about it,so I don 't think so they will listen to you but it s always worth trying.
  4. In TEXAS you have to have your FPGEC certificate before you can apply for your NAPLEX but still you can do it before internship.
  5. Guys don't worry about the calculations or calculator but you should be able to do simple calculations like multiplication,divsion,%. Also don 't spend too much time on calculations 3 days will be more than enough or you can spend 1 hr everyday for a week. Remember log and antilog of 1,10,100 also try to do all the simple formulas problem from Mannan sharof and you should also learn em. Best of luck
  6. By the grace of Almighty I got 89.
  7. AlAHMED I also appeared dec 06 FPGEE and I ve booked TOEFL for 23 jan.I am also living in texas ,you asked someone to think twice if you want to come to texas.I wondered if you have any information if we can start internship without FPGEC certification??as I ve been keep emailing them but they don't answer. please reply
  8. Alahmed i need your help or anyone who know the answer please explain me Q:Which of the following pairs of molecules would most likely exhibit a dipole-induce dipole interaction? a.Benzene,Hexane b.Benzene,Benzene c.Ethanol,Ethanol d.Ethanol,Banzene Q:Which of the following compounds has lowest numerical Pka value? a.Phenol b.p-Nitrophenol c.p-Methoxyphenol d.p-Methylphenol Thanks in advance
  9. Ion Concentration in cytosol (millimolar) Concentration in blood (millimolar) Potassium 139 4 Sodium 12 145 Chloride 4 116 Bicarbonate 12 29 Amino acids in proteins 138 9 Magnesium 0.8 1.5 Calcium 1.8
  10. One of my friend recently passed APEC PART 1,she sent me.I am unable to contact her as i ve lost her contact.
  11. Few weeks back one of my friend sent me.Actually she recently passed APEC first part(australian pharmacy). But i am not in contact with her so unable to find exact answers.
  12. Can someone tell me nearest hotel to chicago test center.Please tell me address or tel no. Thanks
  13. If someone knows answer of following please share 1. In a conjugated protein, a prosthetic group is: A) a part of the protein that is not composed of amino acids. B) a fibrous region of a globular protein. C) a subunit of an oligomeric protein. D) synonymous with "protomer." E) a nonidentical subunit of a protein with many identical subunits. 2. 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 3. The functional differences, as well as differences in threedimensional structure, between two different enzymes from E. coli result directly from their different: A) roles in DNA metabolism. B) amino acid sequences. C) secondary structures. D) roles in the metabolism of E. coli. 4. Even when a gene is available and its sequence of nucleotides is known, chemical studies of the protein are still required to determine: A) the location of disulfide bonds. B) the number of amino acids in the protein. C) the amino-terminal amino acid. D) molecular weight of the protein. E) whether the protein has the amino acid methionine in its sequence. 5. A biochemist is attempting to separate a DNA-binding protein (protein X) from other proteins in a solution. Only three other proteins (A, B, and C) are present. The proteins have the following properties: pI (isoelectric size bind to point) Mr DNA? ------------------------------------------------------------- protein A 7.4 82,000 yes protein B 3.8 21,500 yes protein C 7.9 23,000 no protein X 7.8 22,000 yes ------------------------------------------------------------- What type of protein separation techniques might she use to separate: (a) protein X from protein A? (b) protein X from protein B? © protein X from protein C? 6. Define the primary structure of a protein. 7. A polypeptide is hydrolyzed, and it is determined that there are 3 Lys residues and 2 Arg residues (as well as other residues). How many peptide fragments can be expected when the native polypeptide is incubated with the proteolytic enzyme trypsin? 8. The four peptides below resulted from fragmenting a larger polypeptide. Each of the four fragments was separated and sequenced. Determine the sequence of the original polypeptide. Fragment 1 IKGGPM Fragment 2 GAAWHDFIPRGA Fragment 3 QCVHGA Fragment 4 IPRGAALIKGG 9. All of the following are considered "weak" interactions in proteins except: A) van der Waals forces. B) hydrogen bonds. C) ionic bonds. D) peptide bonds. E) hydrophobic interactions. 10. In an aqueous solution, protein conformation is determined by two major factors. One is the formation of the maximum number of hydrogen bonds. The other is the: A) formation of the maximum number of hydrophilic interactions. B) maximization of ionic interactions. C) minimization of entropy by the formation of a water solvent shell around the protein. D) placement of polar amino acid residues around the exterior of the protein. E) placement of hydrophobic amino acid residues within the interior of the protein. 11. Which of the following best represents the backbone arrangement of two peptide bonds? A) Ca-N-Ca-C-Ca-N-Ca-C B) Ca-N-C-C-N-Ca C) C-N-Ca-Ca-C-N D) Ca-C-N-Ca-C-N E) Ca-Ca-C-N-Ca-Ca-C 12. Which of the following groups correctly shows intrachain hydrogen bonding ||| in an à helix? A) -N-H|||H-NB) -C=O|||H-CC) -C=O|||H-ND) -N-H|||H-RE) -C=O|||O=C- 13. Thr and/or Leu residues tend to disrupt an à helix when they occur next to each other in a protein because: A) of electrostatic repulsion between the Thr and/or Leu side chains. B) both amino acids are highly hydrophobic. C) the R group of neither amino acid can form a hydrogen bond. D) of steric hindrance between the bulky Thr and/or Leu side chains. E) of the possible covalent interactions between the Thr and/or Leu side chains. 14. An average protein will not be denatured by: A) sodium dodecyl sulfate. B) pH 10. C) heating to 90°C. D) urea. E) iodoacetic acid. 15. Determination of the precise spacing of atoms within a large protein is possible only through the use of: A) a Ramachandran plot. B) molecular model building. C) x-ray diffraction. D) light microscopy. E) electron microscopy. 16. Which of the following statements about oligomeric proteins is false? A) All subunits must be identical. B) Some subunits may have nonprotein prosthetic groups. C) A subunit may be very similar to other proteins. D) Some oligomeric proteins can further associate into large fibers. E) Subunits can exist in dozens or even hundreds of genetic variations. 17. The major driving forces involved with the formation of very large multiunit protein complexes, for example the protein capsid of a virus, are: A) free energies of hydrolysis of such molecules as ATP and GTP. B) the same weak, noncovalent interactions that determine the native conformation of a single polypeptide. C) the free energies of binding by small ligands. D) entropy increases resulting from the formation of many new peptide bonds. E) entropy decreases resulting from the formation of symmetric crystalline shapes, for example, icosahedrons. 18. Describe briefly what is meant by primary, secondary, tertiary, and quaternary protein structure. 19. Any given protein is characterized by a unique primary structure and tertiary structure. Define primary and tertiary structure and describe very briefly how they are related in proteins. 20. How do disulfide bridges contribute to a protein's native conformation? 21. Describe three of the important features of a á-pleated sheet polypeptide structure. Provide one or two sentences for each feature. 22. Explain (succinctly) the theoretical and/or experimental arguments in support of this statement: "The primary sequence of a protein determines its three-dimensional shape and thus its function." 23. When hemoglobin crystals prepared in the absence of oxygen are exposed to oxygen, they shatter. Why, in molecular terms? 24. In many organisms, one of the enzymes required for glycolysis, aldolase, requires Zn2+ to catalyze the isomerization of dihydroxyacetone phosphate and glyceraldehyde-3-phosphate. Under conditions of zinc deficiency, when the enzyme may lack zinc, it would be referred to as the aldolase: A) holoenzyme. B) prosthetic group. C) apoenzyme. D) coenzyme. E) substrate. 25. Which of the following statements is true of enzyme catalysts? A) To be effective, they must be present at the same concentration as their substrate. B) They can increase the equilibrium constant for a given reaction by a thousand-fold or more. C) They lower the activation energy for conversion of substrate to product. D) Their catalytic activity is independent of pH. E) They are generally equally active on D and L isomers of a given substrate. 26. Which of the following kinetic parameters remains the same for S --> P, whether the reaction is enzyme-catalyzed or uncatalyzed? A) k B) V C) V0 D) Keq' 27. The steady state assumption, as applied to enzyme kinetics, implies: A) Km = Ks. B) the maximum velocity occurs when the enzyme is saturated. C) the ES complex is formed and broken down at equivalent rates. D) the Km is equivalent to the cellular substrate concentration. E) the enzyme is regulated. 28. To calculate the turnover number of an enzyme you need to know the: A) initial velocity of the catalyzed reaction at low . B) initial velocity of the catalyzed reaction at >> Km. C) Km for the substrate. D) enzyme concentration. E) both B and D. 29. Michaelis and Menten assumed that the overall reaction for an enzyme-catalyzed reaction could be written as k1 k2 E + S ----> ES ----> P k-1 Using this reaction, the rate of breakdown of the enzyme-substrate complex can be described by the expression: A) k1([Et] - [ES]). B) k-1[ES] + k2[ES]. C) k2[ES]. D) k-1[ES]. E) k1([Et] - [ES]). 30. Which of the following statements about a plot of V0 vs. for an enzyme that follows Michaelis-Menten kinetics is false? A) Km is the at which V0 = 1/2 Vmax. B) the shape of the curve is a hyperbola. C) the y-axis is a rate term with units of mm/min. D) as increases, the initial velocity of reaction, V0 , also increases. E) at very high , the velocity curve becomes superimposed on a horizontal line which intersects the y-axis at Vmax. 31. Allosteric enzymes: A) usually have only one active site. B) are regulated primarily by covalent modification. C) usually have more than one polypeptide chain. D) usually show strict Michaelis-Menten kinetics. E) usually catalyze several different reactions within a metabolic pathway. 32. What is the difference between an enzyme "cofactor" and an enzyme "coenzyme"? 33. For a reaction that can take place with or without catalysis by an enzyme, what would be the effect of the enzyme on the: (a) standard free energy change of the reaction? (b) activation energy of the reaction? © initial velocity of the reaction? (d) equiibrium constant of the reaction? 34. Give the Michaelis-Menten equation and define each term in it. Does this equation apply to all enzymes? If not, to which kind does it not apply? 35. Methanol (wood alcohol) is highly toxic because it is converted to formaldehyde in a reaction catalyzed by the enzyme alcohol dehydrogenase: NAD+ + methanol ---> NADH + H+ + formaldehyde Part of the medical treatment for methanol poisoning is to administer ethanol (ethyl alcohol) in amounts large enough to cause intoxication under normal circumstances. Explain this in terms of what you know about enzyme mechanisms. 36. Why does pH affect the activity of an enzyme?
  14. Can we all meet for couple of hours to refresh ourselves?
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