Assertion: testis's germ cell | /r/CapableOf | form cluster
Facets:
value: in the center of the vesicle
type: LOCATION
Source sentences:
text: In the testicular rudiment, germ cells did not show any epithelial arrangement but formed a cluster in the center of the vesicle; somatic cells were not present among the germ cells but constituted a single layer of epithelium encircling the vesicle ( Fig. 2b).