No you don't understand how a neuron works fully or else you'd be able to make a synthetic one from chemical building blocks not using another living thing to do it. If you used another living thing to do it, you could say an ancient farmer understands plants cause they can put seeds in the ground. You have an incomplete model of it that is wrong but useful. Call me back when you can 3d-print a living person from raw chemical feedstock.
On top of all that, you're abusing the fallacy of composition. The bolt that is part of the aircraft carrier is light, therefore the aircraft carrier is also light. The atom is simple, therefore a living human being that is composed of atoms is also simple. Quantum mechanics is influenced by the observer, therefore you can change the external world just by thinking, and other new age stuff like that abuses a similar fallacy.
On top of all that, you're abusing the fallacy of composition. The bolt that is part of the aircraft carrier is light, therefore the aircraft carrier is also light. The atom is simple, therefore a living human being that is composed of atoms is also simple. Quantum mechanics is influenced by the observer, therefore you can change the external world just by thinking, and other new age stuff like that abuses a similar fallacy.