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Related to trochal: trochal disk, trochal disc


Shaped like or resembling a wheel, as the ciliated ring of a rotifer.

[From Greek trokhos, wheel; see troche.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Zoology) zoology shaped like a wheel: the trochal disc of a rotifer.
[C19: from Greek trokhos wheel]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
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References in periodicals archive ?
Once released from the brood tube, the planktonic larvae locomote within the water column using their ciliary trochal bands.
In many spiralians, the embryo passes through a trochophore or a trochophore-like larval stage, characterized by a transverse belt of ciliated, trochal cells.
The stomadeum, velar lobes, and gut in gastropods compared to the trochal ciliated bands and gut in Capitella sp.
Chaetopterus pugaporcinus lacks ciliated trochal bands, a key larval characteristic.
Metamorphosis in this species is not morphologically dramatic, but includes a pronounced elongation, loss of trochal bands and accompanying locomotory changes, and a transition from non-feeding to feeding.
Ciliary structures: apical tuft present; one pair of lateral hooked cilia; trochal band absent
Expression of the reporter gene appeared to be limited to the trochal cells, and began about 30 minutes after the appearance of tubulin mRNA (3).
columbiana at 10-12 [degrees] C Age Stage [approximately]6 h First cleavage 18 h 4 cells 24 h 8 cells 48 h Round blastula 2-3 days Gastrulation: blastula flattens and then forms a horseshoe-shaped gastrula 3-7 days Gastrula 8 days Foot and head rudiments begin to differentiate, some trochal ciliary motion; the shell is not yet present 10 days Shell, cilia, and foot with operculum and statocysts present, light red PMO just visible 17 days Heartbeat and ciliary motion in gut visible 19 days Veligers hatch, PMO is black 72-80 days Veligers begin to crawl [approximately]90 days Settlement and metamorphosis Individual eggs are white and range from 71 to 77 [[micro]meter] in diameter (mean = 74.5; SD = 1.61; n = 23).