AIntFIG 5: Compression of the intestine during aging.
A. Transverse cross-section of 15-day-old (class B) nematode showing extreme compression of the intestine between the gonad and the body wall, such that the cytoplasm consists of a faint narrow electron dense stripe surrounding the lighter lumen. No evidence of cytoplasmic organelles can be detected here. (Image source: N816 [Hall] H0027.)
B. Longitudinal section of 15-day-old (class B) adult nematode showing some compression of the intestine and degradation of the cytoplasm of the intestine. There are many vacuoles and lighter-staining vesicles filling the cytoplasm, but rather little ground substance surrounding them. The dark circular object along the right edge of the intestine is not a nucleus, but a fragment of distal germline poking into the intestine. (Image source: N815 [Hall] G702.)
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