oesophagus+to+stomach

Ensure you explain the structure and function of the oesophagus and stomach. red - means inaccurate blue = corrections to be made

=__**The Oesohagus To The Stomach**__=

=The Oesophagus=

===The oesophagus is an organ which is found in animals with back bones (vertebrates) which consists of a muscular tube through which food passes from the pharynx to the stomach. The oesophagus is also known as the gullet. The function of:===

http://www.youtube.com/watch?v=rJS-Kh5wCQU
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Sphincters prevent materials from moving backward or allow materials to move from one segment of the digestive system into the next a little at a time.
===The cardiac (esophageal) sphincter keeps materials from splashing back up into the esophagus (as it occur acid reflux); the pyloric sphincter prevents the entire stomach contents from entering the duodenum all at one time:===

(and it is easier for bile secretions to neutralise small portiond of acidic chyme).

 * Mechanical digestion and** Chemical digestion

__**MECHANICAL DIGESTION**__
=== An example of Mechanical digestion is the process by which the __teeth in the mouth__ __crush up food into smaller pieces but it still remains the same substance__ it was before it was eaten. In mechanical digestion the main parts involved are the teeth and stomach also bile .This is important as it is easier for the stomach and small intestines that follow to digest this food using chemical digestion.===

__**CHEMICAL DIGESTION**__
===Chemical digestion is the process by which the saliva in the mouth makes food smaller but also changes the food into another substance that the body can use. In chemical digestion the main parts involved with this process are from the mouth all the way up to the ileum. Chemical digestion is important as it - (is necessary as the body would not be able to function the body would not) - provides and makes available via absorption the vital nutrients needed for survival.===

Here is a diagram to shows chemical digestion. and mechanical digestion in the body :


=Peristalsis In The Oesophagus=

===Peristalsis is a series of organized muscle contractions that occur throughout the digestive tract. This mechanical action has to do with sets of muscles that work together to move both liquid and solid food along the digestive tract. Gravitational pull is reduced when food enters the oesophagus because of peristalsis. Peristalsis helps a person to swallow lying down or even standing on their head.=== ===Peristalsis has another important task besides assisting in the movement of food through the body. It also helps to knead, agitate and pound the solid residue that is left after the teeth or for those without teeth, the gums, have done their best when grinding and pounding it to small pieces.=== ===The process looks similar to an earthworm propelling itself through the ground. The muscle contracts creating a narrowing that slowly moves down the length oesophagus. It take approximately 8-9 seconds for the food to travel from the mouth, through the oesophagus and then to the stomach.=== ===If the bolus of food does not reach the stomach in the first set of waves, it activates a second set of waves with the high possibility of reaching to the stomach, also delaying the time to get to the stomach. This may occur with "under-chewing" food, eating foods that are difficult to chew or sometimes, gobbling your at a very short period of time as the food may clump close together and may be difficult to go down.===

Here are images demonstrating peristalsis in the oesophagus:


=The Gastric Pit=

⦁ The chief cells which secrete pepsinogen are stained dark and are deep in the mucosal layer.
fair explantion throughout
 * 1) format was fair excet for the separation of info about the oesophagus
 * 2) error in title of diagram showing only chemical digestion betweenenzymes and major nutrients
 * 3) the flow chart did not suggest names of enzymes associated with protein digestion especially related to the stomach
 * 4) reasons or importance of chemical digestion needed clarity
 * 5) the actual function of enzyme pepsin and HCl was not discussed

good info that describes the oesophagus stomach but
 * 1) no clarity and link made with the terms chemical and mechanical digestion
 * 2) no mention of the epiglotis and its importance to direct food down the oesophagus
 * 3) error or lack of clarity about the exact function of HCl it does not 'digest food'