opportunism

n. the ability to exploit a variety of resources as they become available in changing environmental conditions or different locations. Some species are able to utilize new food resources rapidly: Kelp gulls introduced in Argentina rapidly expanded in numbers by feeding on refuse from fish factories and subsequently learned to attack and eat flesh from whales calving and nursing young in nearby waters. Other species show no opportunism and cannot exploit novel habitats or food resources.

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Psychology term of the day

September 8th 2024

NMDA receptor

a type of glutamate receptor that binds NMDA as well as glutamate. NMDA receptors are coupled to ligand-gated ion channels and are also voltage-sensitive, which enables them to participate in a variety of information-processing operations at synapses where glutamate is the neurotransmitter. The drugs of abuse ketamine and PCP are antagonists at NMDA receptors, preventing the influx of calcium ions at calcium channels, which may cause the hallucinogenic effects of these drugs. Excessive flow of calcium ions into the presynaptic neuron via the NMDA receptor is thought to contribute to glutamate toxicity. A hypothesis on the etiology of schizophrenia involves dysfunction of the NMDA glutamate receptor (see glutamate hypothesis). Compare AMPA receptor.