Final Answer:
The NMDA receptor is voltage-dependent and ligand-dependent.The correct option is voltage; neurotransmitter and -ligand; ion.
Step-by-step explanation:
The NMDA receptor is a crucial component in the regulation of synaptic plasticity and memory formation. Its unique properties make it distinct from other ionotropic glutamate receptors. In this context, the receptor is voltage-dependent, meaning that its activation is influenced by the membrane potential of the postsynaptic neuron. Specifically, the opening of the NMDA receptor channel is facilitated when the postsynaptic membrane is depolarized, allowing for the influx of positively charged ions such as Na⁺.
Furthermore, the NMDA receptor is ligand-dependent, responding to the binding of specific neurotransmitters. Glutamate, a major excitatory neurotransmitter in the central nervous system, serves as the primary ligand for the NMDA receptor. When glutamate binds to the receptor, it initiates a conformational change that allows ions, such as Ca²⁺, to enter the postsynaptic neuron.
This dual dependence on both voltage and ligand ensures that the NMDA receptor is activated in a precise and controlled manner, contributing to the intricate regulation of synaptic transmission.
In summary, the NMDA receptor's functionality is governed by its voltage-dependent nature, responding to changes in the membrane potential, and its ligand-dependent activation, initiated by the binding of neurotransmitters like glutamate. This dual dependency allows the NMDA receptor to play a key role in synaptic plasticity, learning, and memory processes in the brain.
The correct option is voltage; neurotransmitter and -ligand; ion.