An organophosphate inhibits which enzyme that affects the nervous system?

The correct choice is cholinesterase, which is the enzyme inhibited by organophosphates. Organophosphates are a class of chemicals commonly used as insecticides, and they exert their effects by interfering with the normal functioning of the nervous system. Specifically, they inhibit cholinesterase, the enzyme responsible for breaking down acetylcholine in the synaptic cleft.

When cholinesterase is inhibited, acetylcholine accumulates at the neuromuscular junction and synapses, leading to prolonged stimulation of the muscles, glands, and the central nervous system. This can result in a range of symptoms, including muscle twitching, respiratory distress, and even death, depending on the level of exposure and the dose of the organophosphate.

Other options involve enzymes that serve different functions. Cyclooxygenase is involved in the inflammatory response and the synthesis of prostaglandins, phospholipase plays a role in membrane lipid metabolism and inflammatory processes, and carboxylase is involved in various metabolic pathways, including fatty acid synthesis. None of these directly relate to the mechanisms by which organophosphates affect the nervous system. Therefore, the inhibition of cholinesterase is the key to understanding the neurotoxic