If a blood clot forms, it can stop the blood flow. This can cause a heart attack or stroke. A heart attack occurs when the blood flow to a part of the heart is blocked by a blood clot. If this clot cuts off the blood flow completely, the part of the heart muscle supplied by that artery begins to die.
Digestion works by moving food through the GI tract. Digestion begins in the mouth with chewing and ends in the small intestine. As food passes through the GI tract, it mixes with digestive juices, causing large molecules of food to break down into smaller molecules.
Digestion. Digestion is the breakdown of food into simpler molecules that can be absorbed by the body. The digestive system is actually a long hollow tube called the gastrointestinal tract, or GI tract. The digestive system includes the mouth, pharynx, esophagus, stomach, small intestine, and large intestine. Several major glands include the salivary glands, the pancreas, and the liver. The first task of the digestive system is to break down food into a fine pulp (mechanical digestion). When the food is physical broken down, digestive chemicals break the food down into small molecules (chemical digestion). The mouth is the organ in which the process of digestion begins.