Final answer:
Emesis, or vomiting, is the forceful expulsion of food through the mouth due to an irritant affecting the digestive tract. It is regulated by the medulla and caused by strong contractions of the stomach muscles. Various factors can trigger emesis, including viruses, bacteria, emotions, sights, and food poisoning.
Step-by-step explanation:
Emesis, or vomiting, is the forceful expulsion of food through the mouth in response to an irritant affecting the digestive tract. This process is regulated by the medulla and is caused by strong contractions of the stomach muscles. It can be triggered by various factors, including viruses, bacteria, emotions, sights, and food poisoning.