Finally, as the digestive canal is a complex system, a series of separate chemical laboratories,...#Ivan Pavlov
Edible substances evoke the secretion of thick, concentrated saliva. Why? The answer, obviously, is that...#Ivan Pavlov
But man has still another powerful resource: natural science with its strictly objective methods.#Ivan Pavlov
The physiologist who succeeds in penetrating deeper and deeper into the digestive canal becomes convinced...#Ivan Pavlov
