BCH 451 Final Exam Newest Actual Exam

pg. 1 BCH 451 Final Exam Newest Actual Exam Questions with Correct Verified Answers/ Graded A+

____ is the primary force of potein structural stabilization. - Correct Answer - Hydrophobic effect

The ____ is the characteristic speed of an enzyme's kinetics extrapolated to a time when a defined amount of substrate is added to the enzyme solution. - Correct Answer - Initial rate

An act of ____ does not change an enzyme and lowers the transition state free energy of the associated reaction. - Correct Answer - Catalysis

The ____ of an enzymatic catalysis reaction is the rate achieved when it is saturated with substrate. - Correct Answer - Maximum velocity

The ____ or ____ equation defines the parameters that are used to characterize the kinetics of an enzyme. - Correct Answer - Lineweaver-Burk; double reciprocal

K(m), the substrate concentration when V0=Vmax/2, is also called ____ . - Correct Answer - Michaelis-Menten constant

A ____ is the enzyme-substrate combination formed during an enzyme catalysis event.

• Correct Answer - Michaelis complex

The catalytic rate constant of an enzyme is abbreviated as ___. - Correct Answer - k(cat)

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pg. 2 ____ inhibition of enzyme catalysis occurs when the inhibitor binds to the active site of the enzyme - Correct Answer - Competitive

____ inhibition of enzyme catalysis occurs when the inhibitor only binds to the enzyme- substrate complex. - Correct Answer - Uncompetitive

The ____ postulates that a constant input feed of substrate is supplied whose rate equals that of prouct formation. - Correct Answer - Steady state approximation

Two internal factors that limit the velocity of an enzymatic reaction are ____ and _____.

• Correct Answer - hydrophobic effect, hydrogen bonding, disulfide bonds, van der

Waals forces, salt bridges, or dipole-dipole interactions

Two external factors that limit the velocity of an enzymatic reaction are ____ and ____. - Correct Answer - pH, solvent polarity, temperature, chaotropes, osmolytes, salt concentrtion

What amino acid and functional group in the esterase site of acetylcholine esterase reacts with the substrate? - Correct Answer - serine, hydroxylate

The _____ describes the relation between the interatomic distances, electronic charge, solution dielectric, and free energies. - Correct Answer - van der Waals interaction

Protein ____ structure defines the relationship among subunits in a multisubunit lattice - Correct Answer - Quaternary

Protein _____ structure defines amino acid sequence - Correct Answer - Primary

Protein _____ structure defines the packing of helices, sheets, turns, etc. - Correct Answer - Tertiary

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pg. 3 Protein ____ structure defines motifs formed by short range interactions between amino acids - Correct Answer - Secondary

A ____ involves polar O, N or both and the atom for which it is named, and constitutes one of the important protein stabilization elements. - Correct Answer - hydrogen bond

____ is used to determine the sequence of a protein based on sequential chemical reactivity. - Correct Answer - Edman degradation

A ____ induces denaturation of proteins by disturbing the hydrophobic effect. - Correct Answer - chaotropic agent

A _____ is a graph of the conformational torsion angles phi and upsilon for the residues in a protein or peptide; a map of the structure of the polypeptide bakbone. - Correct Answer - Ramachandran plot

A ____ has two charges which neutralize each other. - Correct Answer – Zwitterion

The coenzyme bound carbohydrates ____ and glucose are require to synthesize lactose. - Correct Answer - UDP-galactose

Cis-retinal functions in ____ the signal of a photon of light into a chemically recognizeable form. - Correct Answer - Transducing

The two important straight chain forms of carbohydrate structures are ___ and ____. - Correct Answer - Aldose; ketose

The two important ring forms of carbohydrates are ____ and ____. - Correct Answer - Pyranose; furanose

The two important ring conformations of Beta-D-glucopyranose are the ____ and the ____ conformations. - Correct Answer - Chair; boat 3 / 4

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The cyclohexane ring containing the compound ____ is release by phospholipase C in the phospholipid signal transduction mechanism. - Correct Answer - Inositol trisphosphate

Th acronym NAG is used to abbreviate the compund ____. - Correct Answer - N-acetyl glucosamine

The key polysaccharide in starch is ____. - Correct Answer - Amylopectin

The key polysaccharide in the liver is ____. - Correct Answer - Glycogen

The antibiotic ____ selectively inhibits cell wall ____ synthesis in bacteria. - Correct Answer - penicillin, peptidoglycan

Extra cellular surface ____ regulate the osmotic pressure around cells. - Correct Answer

• carbohydrates

Phospholipase C produces two different second messengers in the phospholipid signal transduction pathway. The lipid containing second messenger is ____. - Correct Answer

• Diacylglycerol (DAG)

The compound chondroitin sulfate ____ cartilage and skeletal joints. - Correct Answer - Lubricates

Saturated or unsaturated fatty acids of the same length have a lower melting temperature - Correct Answer - Unsaturated

Lipid melting point volues monitor the transformation from ____ to dispersed forms - Correct Answer - Liquid crystal

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