T.S. of Pheretima through the Gizzard

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COMMENTS:

•The section shows organ grade of construction with triploblastic layeration and true coelom.

• Oesophagus terminates into prominent oval, hard, thick-walled and distinct gizzard lying in 8th and 9th segment.

• Body wall is composed of a thin cuticular muscle layer, thick longitudinal muscle bundle, parietal epithelial layer and a thick circular septum, thin cuticular and columnar epithelial epidermis.

• Gizzard is a hard muscular organ, composed of visceral coelomic epithelial layer, thick circular muscle fiber, and lined internally by columnar epithelial cells and thin cuticle. 

• Gizzard is a masticatory apparatus and breaks food into small particles.

• Gizzard can at once be recognized by thick continuous muscle fibre and various blood vessel.

• Section also contains dorsal and ventral vessels, ventral nerve cord, integumentary nephridia and lateral nerve cord, and lateral oesophageal vessels.

• Few muscle strands are also seen in the section.





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