Ask a Teacher
Q:Why vomiting is happening in humans? |
Vomiting is the forceful expulsion of contents of the stomach and often, the proximal small intestine. It is a manifestation of a large number of conditions, many of which are not primary disorders of the gastrointestinal tract. Regardless of cause, vomiting can have serious consequences, including acid-base derangments, volume and electrolyte depletion, malnutrition and aspiration pneumonia. Some of the more common are viral infection, food poisoning, alcohol overdose, alcoholic hangover, morning sickness, motion sickness, gastritis, and reactions to medications. Less common causes are kidney disease, gastrointestinal cancer, intestinal obstruction, concussion, diabetes, appendicitis, and various diseases of the internal organs. The brain is in charge, and muscles adjacent to the stomach do the work. The vomiting center is located in the medulla oblongata, the rear part of the brain. This neural center acts on information supplied by the stomach, the intestines, the gag reflex in the throat, the inner ear, and most importantly, the chemoreceptor trigger zone (CTZ), which is located on the floor of the fourth ventricle in the brain. The CTZ takes in data about the presence of toxins in the blood and alerts the vomiting center to go to work when it believes the body has been poisoned. The stomach and intestines can signal for vomiting to occur when they are irritated or overloaded. |