So this is a very typical drawing for a neuromuscular junction here. So up here are the nerve terminal and then down here are the muscle fibers, muscle cells around here, and then here are synaptic transmission sites. And if we blow this picture up, we can see this structure. So within a synapse, we have pre-synaptic side and we have post-synaptic side. And for both pre and post synaptic sides because the signal transduce needs energy so we have lots of mitochondria distributed around both pre-synaptic side and post-synaptic side. So in the pre-synaptic side, we have vesicles. Synaptic vesicles containing different Types of neurotransmitter in these vesicles. So interestingly, these vesicles like lots of the neurotransmitters co-localized in one vesicle. So meaning one vesicle can contain more than one types of neurotransmitter. So sometimes the glutamate vesicle containing glutamate can also contain some other transmitter like 5-HT. And glutamate we will learn later, glutamate is the major excitatory transmitter. And 5-HT is inhibitory normally. So these neurotransmitters can be co-released by one vesicle. So when you do your further study, especially the electrophysiology recording, you need to pay attention to that. Now only one vesicle for one type of neurotransmitter, and then this is the staining or picture, and there under microscope to see the end plate of the neuromuscular junction. And these big structure here are the synaptic sites. So here is another picture for the end plate of a neuromuscular junction and within this vesicles we have neurotransmitter. And then Calcium signal arrive at the pre-synaptic site, make the pre-synaptic vesicle move towards the presynaptic membrane and then fused with the membrane. And then the neurotransmitter get released to the synaptic space. And this is a picture and their scanning electron microscope for the big trunks here are the muscle fibers, and then these are the end plates for the nerve terminal. And then this is a neuron soma surrounded by synapses, and then these things are the synapses, and the big round thing there are neuron, yes neuron. And here, for example, Acetylcholine. Acetylcholine, the neurotransmitters are wrapped by the synaptic vesicle with ATP produced by mitochondrial, the vesicle can move towards the pre-synaptic membrane. And then vesicle fused with pre-synaptic membrane Acetylcholine get released from the vesicle into the synaptic cleft, and then the acetylcholine freely diffuse into the space between pre-synaptic and post-synaptic membrane. Acetylcholine binds to the post-synaptic acetylcholine receptors here at the muscle cell surface, and then the acetylcholine receptor are activated by upon the ligand binding.