LAB2

• Food is received through the mouth.
• Chewed food are mixed with salivary amylase and mucus and shaped into a lubricated “bolus”; it is now ready for swallowing
• The bolus is forced backward through the mouth and goes down into the pharynx and into the esophagus.
• Food is forced into the stomach through the esophagus by muscular movements known as “peristalsis”.
• Gentle peristaltic movements pass over the stomach are emptied into the small intestine.
• During the passage of intestinal contents through the small intestine, products of digestion together with many other compounds like vitamins, water, mineral salts are absorbed.
• When the contents reach the large intestine, the process of absorption, with the exemption of water, is normally completed.
• In the large intestine, more water and sodium chloride are absorbed and the remaining material leaves the body as feces.
• Stool containers should be covered, clean, wide-mouthed and preferably colorless. It should be free from water, urine and soil.
• Stool examination falls under clinical microscopy in a hospital set-up and thus may not be given priority since there are other specimens to be examined.
• However, in the diagnosis of amoebiasis, consistency of stools dictates that diarrheic or watery stools must be examined within 30 minutes to 1 hour since trophozoites die within this period outside the body of the host.
• If transportation and examination is to be delayed it should be immediately preserved in 10% formalin solution or polyvinyl alcohol (PVA).
• For routine stool examination, 20-40 g of formed stools (usually half of the thumb) or 5 -6 tbsps of watery stools will suffice.
• There are situations when it is necessary to submit the whole stool movement like in cases where the laboratory likes to recover helminthic adults after treatment.
• Necessary to submit the whole stool movement; this is best exemplified by the examination done after Taenia species treatment.