HypFIG 1: Embryonic and post-embryonic lineages.
Although many of the hypodermal and seam cells arise embryonically, more are added during each larval stage (based on Sulston and Horvitz, 1977; Sulston et al., 1983).
A. Embryonic lineage. The major precursor for hypodermal lineages is the AB founder cell, whose daughters have a left-right asymmetry (cf., the lineage patterns of ABarp and Abalp, a major hypodermal precursor and a pharyngeal precursor, respectively). The C founder cell yields other posterior and dorsal hypodermal cells. (Dotted lines) More than one division occurs until final hypodermal cells are born.
B&C. Postembryonically, additional cells that fuse with hyp 7 come from 2 major lineages; seam-precursor divisions (B) and P-cell divisions (C). (Shading) Each molt at 20-22oC. Time at hatching is 0. (X) Programmed cell death; (dt) daughter.
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