Zinc, an Essential Trace Element for Most Organisms, Is Present

question 53

Multiple Choice

Zinc, an essential trace element for most organisms, is present in the active site of the enzyme carboxypeptidase. The zinc most likely functions as ________.

• A) a competitive inhibitor of the enzyme
• B) a noncompetitive inhibitor of the enzyme
• C) an allosteric activator of the enzyme
• D) a cofactor necessary for enzyme activity
• E) a coenzyme derived from a vitamin

---

Definitions:

Pleasure Principle

A concept in psychoanalytic theory referring to the instinctual seeking of pleasure and avoiding pain to satisfy biological and psychological needs.

Id

In psychoanalytic theory, the part of the psyche that is the source of instinctual impulses and demands for immediate satisfaction of primitive needs.

Thanatos

In psychoanalytic theory, the death drive representing an unconscious wish for death or self-destruction.

Conscious Mind

The aspect of the mind that is aware of one's self, thoughts, feelings, and surroundings.