AHypFIG 4: Hypodermal fragmentation in older adults

AHypFIG 4: Hypodermal fragmentation in older adults.

A. Transverse section of young adult at the midbody. Inset (left) shows closeup of the young adult hypodermis (tan) with intracellular contents. Excretory cell (magenta); muscle (green); intestine (pink); nerve cord (orange); gonad (blue). Black arrowhead indicates a hyp nucleus. In the enlargement, the hyp nucleus contains a large dark nucleolus. Bar, 5 microns.
B. Transverse section of day 15 adult. In this adult, most cells have deteriorated. The hypodermis has shredded and remains as fragments. Other cells showing deterioration are the intestine (pink), which has become vacuolated, body muscle sarcomeres (msf, muscle sarcomere fragments) and the gonad or uterine sheath (purple). The white arrowhead labels a nucleus, probably of the seam cell. (B, inset). Closeup of the lateral line region, where the excretory canal (magenta) lies next to structures which could reflect hypodermal deterioration. Three thin sheets of deteriorating hypodermis (tan) are present with rather light cytoplasm and intact small mitochondria. Bar, 5 µm.
(Image sources: A. N506 N279 [D. Hall]; B. N803 E810 [D. Hall]; B (inset) N803 E815 [D. Hall].)

Click on picture for full resolution image.