Read the following statements carefully: I. Electrical synapses are rare in the human neural system. II. At chemical synapses, the arriving action potential stimulates the movement of synaptic vesicles towards the membrane. III. Neurotransmitters bind to specific receptors located on the presynaptic membrane. IV. A fluid-filled space called the synaptic cleft is always absent in chemical synapses. How many of the abo

Step-by-step solution

Statement I is correct as electrical synapses are rare in our neural system. Statement II is correct because the arrival of an action potential at the axon terminal stimulates synaptic vesicles to move towards and fuse with the plasma membrane. Statement III is incorrect because the specific receptors for neurotransmitters are located on the post-synaptic membrane, not the presynaptic membrane. Statement IV is incorrect because the membranes of pre- and post-synaptic neurons at a chemical synapse are separated by a