3rd Lec Exam - Digestive

Question 1

Define Filter feeding (Aquatic). Employed by what organisms?

Answer 1

Oldest craniate method of acquiring food; employed by larval lampreys (& w/ mods., few jawed fishes and baleen whales)

Question 2

Early embryonic digestive tract? Origin?

Answer 2

Foregut, midgut, hindgut; Except epithelial lining, gut forms from splanchnic mesoderm; Epithelium = endodermal origin

Question 3

What do stomodeal and proctodeal invaginations establish?

Answer 3

Entrance (mouth) & exit (vent or anus)

Question 4

The gut is suspended in what?

Answer 4

Within a coelom by a dorsal mesentery that’s continuous with the parietal peritoneum lining the body wall (somatopleure) and with the visceral peritoneum on the surface of the organs

Question 5

Fate of the ventral mesentery

Answer 5

Disappears except the falciform ligament of the liver