The human parotid gland (PG) is developed from an ectodermal proliferation of the stomodeum
during the sixth week of prenatal development (Moore & Persaud, 2002).
Other visible structures are the stomodeum
and the labrum, located in the central portion of the naupliar embryo.
The pharyngeal gut is separated from the stomodeum
by the buccopharyngeal membrane.
During the larval stages, at the junction of the stomodeum
with mesodeum, two pairs of caeca are present--an anterior pair formed by a simple tubule and a lateral pair with three lobes (Fig.
Neuroendocrine tumors would not be expected to occur in tissue derived from the primitive stomodeum
Taxonomic value of the cuticular structures of the stomodeum
These beetles have a typical digestive system divided into three regions: stomodeum
, mesenteron and proctodeum.
The adenohypophysis, or anterior pituitary, is derived from an evagination of oral ectoderm of the dorsal median region of the stomodeum
. The neurohypophysis, or posterior pituitary, is derived from an evagination of the infundibular portion of the diencephalon of the brain.
Ctenophores display features of bilateral symmetry around the oral-aboral axis: the flattened stomodeum
defines the sagittal plane, and an orthogonal tentacular plane passes through the two tentacle pouches.
appeared at stage 13 and the prototrochal girdle with its cilia were completely formed during stage 14 (Fig.