OSMT (Ontario Society of Medical Technologists) Practice Exam

At a synapse, the transmission of a nerve impulse occurs through the release and binding of neurotransmitters. When an action potential reaches the end of a neuron, it triggers the release of these chemical messengers from vesicles into the synaptic cleft, the small gap between two neurons. The neurotransmitters then diffuse across this cleft and bind to specific receptors on the postsynaptic neuron, initiating a response that can result in either excitation or inhibition of that neuron.

This process is crucial for communication between neurons, as it converts the electrical impulse of the presynaptic neuron into a chemical signal. The correct functioning of neurotransmitter release and receptor interaction is fundamental for the nervous system's overall activity, affecting everything from muscle contraction to the processes involved in learning and memory.

Other concepts mentioned, like depolarization, the myelin sheath, and repolarization, are all important in the broader context of nerve impulse conduction but do not specifically describe how the impulse is carried across synapses. Depolarization refers to the change in membrane potential that occurs during an action potential, and repolarization is the phase that restores the membrane potential back to resting levels. The myelin sheath is a protective covering that insulates axons and increases