Answer to Question 1
Believe it or not, the word for this noise is borborygmi. When it gets close to mealtime, the brain sends signals to the stomach causing it to contract. These contractions also cause any food remaining in the lower portion of the GI tract to move towards the rectum. Thus, the movement of the intestine and stomach makes growling and gurgling sounds called borborygmi.
Answer to Question 2
Contrary to popular belief, vomiting is not caused by reverse peristalsis. In fact, the stomach does not play an active role at all. Vomiting occurs when the diaphragm (the main respiratory muscle located beneath the lungs) moves downward and the abdominal muscles contract, creating a powerful force that squeezes the stomach contents upward. This pressure causes the sphincter located between the stomach and esophagus to open, and the contents of the stomach are propelled from the body. Vomiting can be caused by physical and emotional factors that stimulate the vomiting center in the brain.