Answer:
Neonicotinoids are a class of insecticides that work by disrupting the transmission of nerve impulses in insects. The compounds are readily absorbed by plants and are present in pollen and nectar, making them highly toxic to bees and other pollinators.
When neonicotinoids come into contact with insects, they bind to certain receptors in the insects' nervous system, specifically the nicotinic acetylcholine receptors. These receptors are found at the junctions between nerve cells, known as synapses, where they play a key role in transmitting nerve impulses from one cell to the next.
The binding of neonicotinoids to the nicotinic acetylcholine receptors interferes with the normal transmission of nerve impulses at the synapses, leading to paralysis and ultimately death in the affected insects. This mode of action is specific to insects, which is why neonicotinoids are effective at controlling insect pests but are relatively non-toxic to mammals.