Entoderm and its derivatives

Abstract

The entoderm (endoderm, enteroderm) is the inner germ layer of the gastrula; it furnishes the lining epithelia of the digestive system (pharynx, intestine), as well as the parenchymal cells of liver¹, acinar cells of the pancreas, also part of the gills, the pseudobranch (Chapter 15, Figs. 15/10–15/14), the swim bladder, Kupffer’s vesicle (Chapter 14) and part of the pituitary, the adenohypophysis. The hypochord is also thought to be of entodermal origin and is dealt with in Chapter 12. (Fig. 12/4). However, in a recent publication on zebrafish entoderm it was decided that ‘this peculiar tissue...has no obvious association with the gut...but our data show that hypochord is not derived from cells near the margin and implies perhaps that hypochord should not be considered endodermal’ ‘(Warga and Nüsslein-Volhard, 1999)’.

‘Pour bien savoir les choses il faut en savoir le détail.’

La Rochefoucauld