.:When your stomach grumbles, you know that you need food. The digestive system is what sustains our bodies and allows
us to absorb nutrients necessary for living. Like a long train ride, the food you consume makes a journey through many different
areas, stopping at some, and passing quickly through others. This section will Highlight different organs and thier purposes.
.:The Mouth:.
One of the most reasily recognized areas of the digestive tract is the first one: The mouth.
When you gaze into the mouth, the main focus is the teeth. Teeth are bone-like structures in the jaw that help mechanically
break up food. WHile mastication is taking plac,e the salivary glands produce saliva which contains amylase to start breaking
down carbohydrates and sugars. Another commonly identified structure is the tongue. The tongue moves food around the mouth
while it is being chewed, and forms a bolus of food when swallowing takes place.
.:Once someone takes that final 'gulp' the bolus enters the pharynx. Tghe pharynx has three seperate parts known as:
the oropharynx, nasopharynx, and laryngopharynx. The uvula stops food from entereing the nasopharynx and continues its passage
towards its next stop.
.:The Esophagus and Stomach:.
After leaving the laryngopharynx, the food encounters the epiglottis. This small flap of cartilage
stops food from entering the trachea and directs it towards the esophagus. Once it has been properly placed, the bolus enters
a muscular tube known as the esophagus and is pushed through the powerful contraction of smooth muscles. In only a few seconds,
the bolus reaches a pouch known as the stomach.
.:The stomach is an organ that has multidimentional muscle layers for mechanical breakdown of food, as well as cells
that produce different chemicals for chemical breakdown. Once the bolus enters here, the stomach produces hydrochloric acid
and other chemicals for the total breakdown of the bolus. After about 30 minutes of chemical and mechanical destruction, the
bolus is transformed into chyme. This is an acidic substance that is ready to enter the small intestine.
Some structures in the stomach are: The Cardiac Sphincter, cardia, fundus, body, pylorus and
pyloric sphincter.
.:The Small Intestine:.
After leaving the stomach and passing the pyloric sphincter, the chyme will enter the duodenum,
the first part of the small intestine. The duodenum is like a junction where the chyme is attacked by bile and numerous other
shimcals produced by accesory organs like the liver, pancreas and gallbladder. From there peristalsis will move it through
the jeujenum and the ileum. These different parts of the small intestine all absorb the nutrient from the chyme.
.:The Large Intestine:.
After its journey through the small intestine comes to a close, the chyme will encounter the ilececal
sphincter. Once it is allowed passage, the Chyme enters the cecum, the first part of the large intestine.
One will notice the large pocketed surface of the large intestine, these structures are called Haustra and help increase
surface area.
Located on the Cecum is the appendix. The appendix is a, basically, vestigial structure that contains lymph tissue.
After passing the cecum, the chyme enters the Colon. The colon is borken into many parts: The ascending colon, transverse
colon, descending colon and sigmoid colon. After the moisture is absorbed, the chyme is considered fecal matter and is ready
to be disposed of. It enters the rectum, and passes through and exits the body via the anus.
.:The Liver:.
As an accesory organ, one could easily disregard the liver. However, that would be a dire misconception.
The liver is the largest organ in the body. It produces numeros chemicals that aid in digestion as well as things like thrombin,
heparin and prothrombin. The liver is integral to the human body's ability to live. (Hence the name LIVEr)
.:The Pancreas:.
The pancreas is a glandular organ that supports the way the body metabolizes food. It produces
chemicals like glucagon and inslin, as well as digestive enzymes that aid in the breakdown of chyme. This organ is integral
to the understanding of diabetes and blood sugar.
.:The Gallbladder:.
The Gallbladder is a small organ nestly comfortably behind the liver. Its purpose is simple:
Store excess bile from the liver. It may not be vital, but it still serves a purpose in the body.
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