Inhibitory postsynaptic potentials can arise from all of the following except BulGepure oAMH orber: a. direct application of GABA to neurons b. Increased permeability of the cell membrane to both K+ and Cl-10ns c. Increased permeability of the cell,membrane to Na+ ions d. Increased permeability of the nerve membrane to K+ lons e. Increased permeability of the nerve membrane to Cl- ions

The correct answer is c. Increased permeability of the cell membrane to $Na+$ ions.<br /><br />Inhibitory postsynaptic potentials (IPSPs) are a type of synaptic potential that makes a neuron less likely to generate an action potential. They are typically caused by the direct application of GABA (gamma-aminobutyric acid) to neurons (option a), which is an inhibitory neurotransmitter. GABA binds to GABA receptors on the neuron, leading to the opening of chloride (Cl-) channels and the influx of Cl- ions into the cell. This makes the inside of the cell more negative, leading to hyperpolarization and inhibition of action potential generation.<br /><br />Options b, d, and e also describe mechanisms that can lead to IPSPs. Increased permeability of the cell membrane to $K+$ ions (option b) or $Cl-$ ions (option e) can lead to the efflux of $K+$ ions or the influx of $Cl-$ ions, respectively, making the inside of the cell more negative. Increased permeability of the nerve membrane to $K+$ ions (option d) can also lead to the efflux of $K+$ ions, making the inside of the cell more negative.<br /><br />Option c, increased permeability of the cell membrane to $Na+$ ions, would lead to the influx of $Na+$ ions and depolarization of the cell, which would make the neuron more likely to generate an action potential. This is the opposite of what happens during an IPSP, so it is the correct answer.