You don't have to be made of metal to be a machine.
Nerves react to either electrical, chemical, or mechanical stimulus. But no, the body is biological. Carbon ba<x>sed.
Yes. A fantastically complicated mechanism a lot of which we can't get close to replicating, but a mechanism nonetheless.<br />
Human hands are just mindblowing... Next time you're doing something, just take a second to think about what your hands are doing, the strength and dexterity and multitasking they're capable of. Our brains get a lot of credit for making us the species we are, but our hands are marvellous adaptations too.