The Digestive System is an organ system that processes food and extracts nutrients from it. It also eliminates residue. The digestive system is able to do this in four stages known as ingestion, digestion, absorption and defecation. The digestive system has two anatomical subdivisions known as the digestive tract, which includes the oral cavity, pharynx, esophagus, stomach, small intestine, and large intestine, and the accessory organs, which include the teeth, tongue, salivary glands, liver, gallbladder, and pancreas. In following the digestion of a bologna sandwich with mayonnaise and lettuce, and an orange, you are able to see the mechanical and chemical digestion, absorption, circulation, and assimilation of a well balanced meal (Saladin, 954).
When you first begin with the bologna sandwich and orange, the digestion process starts with the mouth, also known as the oral or buccal. The mouth contains the cheek, lips, the tongue, the palate, and the teeth, which all have a part in the digestion process.
English: Flesh fly, from the Sarcophagidae family....
Digestive system with liver
Abomasum"The cheek and lips retain food and push it between the teeth for mastication" (Saladin, 958). With each bite, the tongue maneuvers the sandwich and then the orange between teeth and also prepares it for mastication by releasing a portion of saliva from the lingual glands. The palate aids the tongue in holding and manipulating the sandwich, it also allows you to breathe while you're chewing. The teeth, called the dentition, are composed of the incisors and canines. The incisors are used to bite of pieces of the sandwich and orange and the canines are used to puncture and shred it. The teeth are very important in the mastication process because they crush and grind the food so that you are able to swallow without any problems. Saliva is also important because it moistens the mouth, digests a little starch and...