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Phospholipids diffuse rapidly within and between the two leaflets of a bilayer.

Questions 46-50Membrane fluidity would tend to be increased by

Using a reaction coordinate diagram (G vs. reaction plot), (A) indicate the effect of an enzyme catalyst on DGrxn, DG‡, (3 pts.) and (B) the relative Gs of the substrate (S) and product (P) for a reaction that will occur spontaneously.  This includes indicating the DDG‡, the G of S‡, and the G of ES‡. (3 pts.) (C) Which of these parameters above determine the rate (kinetics) and which determines the direction (thermodynamics) of a chemical reaction? (3 pts.) (D) Circle each of the following effects that are brought about by any enzyme catalyzing the simple reaction S -> P? (2 pts.) (a) Decreased Keq; (b) Increased Keq; (c) Decreased DG‡; (d) More negative DG˚’, (e) Increase k2. (E) Diagram two of the four main types of catalytic mechanisms discussed in class and that are exemplified in the mechanism of serine protease catalysis of the cleavage of a peptide bond. (4 pts.)

Regarding membrane lipid and membrane composition and structure: (A) Diagram and describe the functional group properties of the three primary structural components of membrane lipids, using an actual membrane lipid as an example (note: a full chemical structure is not required, just the chemical name for each portion) (3 pts).  The properties of a lipid bilayer are determined by the structures of the lipid components.  Diagram how you predict the effect of the following on a lipid bilayer: (B) The phospholipids have only one hydrocarbon chain tail instead of two. (3 pts.) (C) All the hydrocarbon tails are unsaturated. (3 pts.) (D) The lipid bilayers found in cells are fluid, yet asymmetrical in the composition of the monolayers (leaflets). Is this a paradox (head scratcher, unexpected) and why or why not? (2 pts.) (E) Diagram and describe how lipid bilayers function as a permeability barrier for polar molecules.  Diagram and describe the relative abilities of gases, small polar uncharged, larger polar uncharged and charged molecules to diffuse through a membrane. (4 pts.)

Use a substitution to find the indefinite integral: ∫5xx2+34 dx{“version”:”1.1″,”math”:”∫5xx2+34 dx”}

have all been designed prior to determining the PGP structure.

Because oxygen transport across a membrane is energetically unfavorable.

do not seem to enhance anticancer drug efficacy.

Evaluate the definite integral: ∫047×2-8x+3 dx{“version”:”1.1″,”math”:”∫047×2-8x+3 dx”}

Questions 1-5For the cartoon representation of a protein structure above it is composed of: