Mississippi Pesticide License Practice Exam

Fipronil is known for its effectiveness in disrupting the insect central nervous system. This pesticide functions as a potent insecticide by blocking the GABA (gamma-aminobutyric acid) receptor, which is crucial for regulating neuronal activity in insects. By inhibiting this receptor, fipronil causes uncontrolled activity in the central nervous system, leading to paralysis and ultimately death in the target insect population.

The other choices represent different classes or types of pesticides. Malathion is an organophosphate insecticide that works by inhibiting acetylcholinesterase, an enzyme critical for nerve function, but it operates differently from fipronil. Copper fungicide is a bactericide and fungicide that works to control fungal diseases in plants, not specifically targeting insect nervous systems. Pyriproxyfen is an insect growth regulator that mimics juvenile hormones and disrupts the life cycle of insects but does not directly affect their central nervous system in the same manner as fipronil. Thus, fipronil is specifically recognized for its targeted action on the central nervous system of insects.