Which vertabrae in the spine connect to your stomach and (lower) digestive tract?
I’m not sure that any of them do. The digestive tract is mainly (maybe exclusively) innervated by the prevertebral ganglia and the vagus nerve, I think.
It also has its own brain.
Literally speaking, vertebrae are bones, which, of course, are not part of the nervous system, or connected to the digestive tract, at all, but I assume that is not what you meant.
To clarify-Nerves connected to which vertebrae lead to the digestive tract? (stomach, intestines, colon, etc.)
Nerves do not connect to vertebrae. But you might find out the answer you are actually looking for if you check out the links I already gave you.
None, as far as I remember. Disregarding the fact that vertebrae are bones not neurons, the only real connection between the central nervous system and the enteric nervous system is Mama Vagus, cranial nerve 10. But the gut can function on its own if CN10 is cut.
The control we feel we have over our digestive system is based on control of the external anal sphincter and our diaphragm which causes bowel movmemts (controlled by the phrenic nerve, cervical nerves C3, C4 and C5).