Example Of Essay On The Six Essential Activities Of The GI Tract Are: Ingestion, Propulsion, Mechanical Digestion, Chemical Digestion, Absorption And Defecation.

Identify and describe the six major processes involved in gastrointestinal (GI) activity?

Ingestion: is the process of taking in food, drinks and medicine, orally, into the digestive tract. Once the solid food is inside the mouth, it is chewed and broken down into smaller particles through a process called mastication. The saliva and its enzymes, help in break down of food particles. The incompletely broken food is them passed on to the next region in alimentary tract by swallowing.
Propulsion: is the mechanism by which food is transported from one region of the GI tract to the next. Some amount of mixing also happens during this process. Peristalsis and segmentation processes help in propulsion of food. Peristalsis refers to the involuntary contraction and relaxation of muscles in the organ wall. Segmentation refers to the movement of food, back and forth in the digestive tract. Segmentation is common in the small intestine, and helps to mix the food with the digestive juices.
3. Mechanical digestion: is the process of breaking down food into smaller particles. Mastication in the mouth, churning in the stomach and segmentation in the small intestine, are examples of mechanical digestion. Mechanical digestion, prepares the food for further degradation by enzymes.
4. Chemical digestion: is the series of catabolic reaction that breaks down food molecules into their constituent monomers like amino acids, simple sugars and free fatty acids. Enzymes and buffers in the mouth, stomach and small intestine help in this process.
5. Absorption: refers to the movement of nutrients from the GI tract to the blood and lymph, by active and passive processes. Majority of the absorption happens in the small intestine.
6. Defecation: is the process of elimination of undigested food particles through the anus in the form of feces.