Exam 5: Properties of Enzymes

In a multienzyme complex the process of directly transferring a product of one reaction to the next active site without allowing it to enter the bulk solvent is termed ________.

Which statement is true about catalytic proficiencies?

The hydrophobic cleft in globular proteins which bind substrate molecules is called the ________.

The (lower,higher)the value of Km,the (less,more)tightly the enzyme is bound to the substrate.

All irreversible inhibitors known are from man-made sources.

Ethanol (CH₃CH₂OH)is an alcohol found in beverages.It is oxidized in the body to acetaldehyde by the enzyme alcohol dehydrogenase.Methanol (CH₃OH),also known as wood alcohol,is converted to formaldehyde by the same enzyme.Acetaldehyde is toxic,but formaldehyde is far more toxic to humans,which is why the ingestion of relatively small amounts of methanol can cause blindness or death.One treatment for mild methanol poisoning is the administration of ethanol.Why might a doctor choose this treatment?

Allosteric modulators bind covalently to the regulatory site of an enzyme and change its conformation.

An inhibitor binds to a site other than the active site of the enzyme.Which statement below correlates with this observation?

Select the correct class of enzyme for each of these reactions. -Polypeptide + H₂O → Amino acids

Two curves showing the rate versus substrate concentration are shown below for an enzyme-catalyzed reaction.One curve is for the reaction in the presence of substance X.The other curve is for data in the absence of substance X.Examine the curves and tell which statement below is true.

Enzyme reactions that require all the substrate to be present before any product is released are called ________.