Ethylene glycol (HO—CH₂—CH₂—OH) is a major component of antifreeze. If ingested, it is first converted to HOOC—CHO (oxoethanoic acid) and then to HOOC—COOH (oxalic acid), which is toxic.
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b. The treatment for the ingestion of ethylene glycol is an intravenous solution of ethanol. How might this help prevent toxic levels of oxalic acid in the body?

Methanol and ethanol are oxidized by alcohol dehydrogenase. In methanol poisoning, ethanol is given intravenously to prevent the formation of formaldehyde that has toxic effects.

b. Would ethanol compete for the active site or bind to a different site?

In humans, the antibiotic amoxicillin (a type of penicillin) is used to treat certain bacterial infections.

a. Does the antibiotic inhibit enzymes in humans?

Oxaloacetate is an inhibitor of succinate dehydrogenase. 

a. Would you expect oxaloacetate to be a competitive or a noncompetitive inhibitor? Why?

In humans, the antibiotic amoxicillin (a type of penicillin) is used to treat certain bacterial infections.

c. Is amoxicillin a reversible or irreversible inhibitor?

How does an irreversible inhibitor function differently than a reversible inhibitor?

Indicate whether each of the following describes a competitive or a noncompetitive inhibitor.

e. Adding more substrate to the reaction restores the enzyme activity.

Indicate whether each of the following describes a competitive or a noncompetitive inhibitor.

a. The structure of the inhibitor is similar to that of the substrate.

Indicate whether each of the following describes a competitive or a noncompetitive inhibitor.

c. The inhibitor competes with the substrate for the active site.