MEDICAL PHYSIOLOGY

Detailed explanation-1: -Ionotropic receptors, also called neurotransmitter-gated or ligand-gated channels, are ion channels that open in response to the binding of a neurotransmitter. They are primarily located along the dendrites or cell body, but they can be present anywhere along the neuron if there is a synapse.

Detailed explanation-2: -Answer and Explanation: The answer is a. Graded potentials can form on receptor endings in response to different stimuli and be used for sensory perception and motor control. Postsynaptic potentials are graded potentials that originate in the postsynaptic neuron.

Detailed explanation-3: -When neurotransmitter molecules bind to receptors located on a neuron’s dendrites, ion channels open. At excitatory synapses, this opening allows positive ions to enter the neuron and results in depolarization of the membrane-a decrease in the difference in voltage between the inside and outside of the neuron.

Detailed explanation-4: -A graded potential is produced when a ligand opens a ligand-gated channel in the dendrites, allowing ions to enter (or exit) the cell. For example, Na+ will enter the cell and K+ will exit, until they both reach equilibrium.