A Study Of The Anatomy, Histology, And Histochemistry On The Digestive Tract Of The Marphysa Sanguinea

Anatomical, histological and histochemical methods were used on the preliminary studies on the form, the organization and the location of relevant digestive enzyme digestive tract of Marphysa sanguinea.Morphological and histological studies tell us that the digestive tract of Marphysa sanguinea is short, which is of typical features of omnivorous animals, and can be divided into cavum oropharyngeum, esophagus, intestine with digestive diverticuta and caudal intestine.The epithelia of cavum are stratified pavement epithelia. The digestive tract after the pharynex can be divided into four layers which are mucous layer, tunica submucosa, muscular layer and ectal membrance, in which the most important change is mucousa epithelia. Esophagus has stratified pavement epithelia, too. Mucousa epithelia of intestine and digestive diverticuta are mainly psendostratified columnar epithelia. The structures of intestine has plentiful villi ,which is mainly composed of high columnar epithelia with more striated border and less cilia. Muscles out of digestive diverticuta are thin but at the same time blood vessels are much more rich. Caudal intestine is slender and short, which has pseudostratified ciliated columnar epithelium .The presence of abundant alkaline phosphatse activity in the free end of the epithelia and striated border of the esophagus, intestine and digestive diverticula suggest that these cells were actively involved in absorption of food materials. The absorptive and digestive role is supported by the presence of an intense acid phosphatase in the epithelium of the esophagus, intestine and digestive diverticula. The lipase and esterase were detected in the intestine. Only neutyal mucouscells and a few acidic mucous cells can be found in the intestinal epithelia and digestive diverticula, which can support more evidence that gastrovascular cavity is the main posotion on food' s digestion. There are many mucous cells in the whole digestive tract, this mucosubstances play important role in both digestion and absorption of nutrient.