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    Biological Chemistry

    Short essays in biochemistry

    Short essays: A. Discuss the various components of protein structure (ie, the final three-dimensional shape is the final result of these components of structure). What is denaturation of a protein? B. Discuss how a soap works to cut grease. Diagram a glob of grease which has been emulsified by micelle formation. C. C


    What tripeptide would be synthesized from the informational strand of DNA with the sequence 5' GTATCCAGT? The beta-chain of hemoglobin is a protein that contains 146 amino acid residues. What minimunm number of nucleotides must be present in a strand of mRNA that is coded for this protein?


    The typical length of a DNA strand is 3.4cm. In order to fit into a cell, the DNA strand is supercoiled around proteins called histones. Histones are a family of five proteins thet are rich in the amino acids and lysine. How do histones stabilize the DNA strand? (look at the backbone of the DNA strand at the molecular level.)

    Drawing Structures of Tetrapeptides

    How to draw the structure of this tetrapeptide: Ala-Ser-Tyr-Thr What type of bonding between amino acid residues is most important in holding a protein and polypeptide in a specific secondary configuration?

    Explanation for the Chemical Structure of Hydrocortisone

    Can you please explain the chemical structure of cortisol and hydrocortisone? What is the difference on the structure? How many functional groups hydrocortisone has and what are they? What's in the chemical structure of hydrocortisone that makes it relieves the swelling and inflammation in the skin? Can you please explain

    Threonine & Leucine

    Which of the amino acids, threonine and leucine, would you expect to find on the inside of a globular protein and which would you expect on the outside, if either? Why?

    Tripeptide Protein: Acidic, Basic, or Neutral?

    Alanine has an R-group structure of CH3, cysteine has an R-group structure of HS-CH2, and aspartic acid has an R-group structure of HOOC-CH2 Write out the structural formula for this tripeptide, asp-ala-cys. Is the tripeptide basic, acidic, or neutral? How can you tell?

    Current through proteins

    A direct current was passed through a solution containing alanine, histidine, and aspartic acid at a pH of 6.0. One amino acid migrated to the cathode (+) and one migrated to the anode (-) and the other remained stationary. Match the behavior with correct amino acid. The isoelectric point of histidine is 10.0.

    Proteins: Primary vs. Secondary Structures

    Can there be a secondary structure without a primary structure? Why or why not? Can there be a primary structure without a secondary structure? Why or why not? What types of bonds are responsible for the secondary structure of a protein? How would the addition of a heavy metal affect the secondary structure of a protein?

    Primary structure of glucagon

    Glucagon His-ser-glu-gly-thr-phe-thr-ser-asp-tyr-ser-lys-tyr-leu-asp-ser-arg-arg-ala-gln-asp-phe-val-gln-trp-leu-met-asn-thr Which of the amino acids in the molecule would you expect to be on the inside of the protein? Why?

    Are Albumins Polar or Nonpolar?

    Blood is essentially an aqueous solution but it must transport a variety of non polar substances (hormones for example). Colloidal proteins, termed albumins, facillitate this transport. Must these albumins be polar or nonpolar?

    Lidocaine and Bonding to Receptors

    Draw abbreviated structural formulae of the products of the complete hydrolysis of lidocaine, and identity the functional groups from the first diagram attached. Lidocaine is thought to bond to receptors in its methylated form. Identify in writing the atoms or groups that could be involved in its bonding to a receptor via h

    Chemistry Problem Set: Molecular Behaviour

    Are the following questions true or false? a) A carboxylic acid favours the ion form (R-COO-) and its pH is higher than its pKa. b) In most membranes, the polar heads of the phospholipids align towards the middle of the membrane. c) All proteins contain either an alpha helix or beta sheets.

    Understanding molecular behaviour

    Are the following statements true or false? If false, explain why. a) In most globular proteins, the nonpolar amino acids tend to be concentrated at the surface of the protein. b) A small organic molecule required by an enzyme in order for the enzyme to be a functional catalyst is known as a vitamin. c) Lipids that are

    Construct Standard Curve And Identify Unknown Sample's Value

    Construct a standard curve from a data set and find the concentration of an unknown sample. The following data was obtained using spectrophotometry: Absorb.----------- ug/ml protein 0--------------------------0 0.22--------------------100 0.098-------------------50 0.086-------------------25 0.038------------------12.5