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Related to cnida: nematocyst, Cnidocyst


(Zoology) zoology a nematocyst


(ˈnaɪ də)

n., pl. -dae (-dē).
a nematocyst.
[1875–80; < Latin cnīdē nettle < Greek knidē]
References in periodicals archive ?
When properly acted upon by the supporting cells, the cnidocyte initiates the rapid eversion of its cnida, a process termed discharge.
t] is measured as the adhesive force in the absence of all cnida discharge (Thorington and Hessinger, 1996, 1998).
This view has been reinforced by more recent work on the identification and characterization of chemoreceptors involved in predisposing cnida discharge (Thorington and Hessinger, 1988a, b, c; Watson and Hessinger, 1989).
Nematocysts, one of three types of cnida, are intracellular capsules produced only by members of the phylum Cnidaria (e.
In spite of many quantitative studies of cnida size (Stephenson, 1929; Chintiroglou, 1996; Chintiroglou and Simsiridou, 1997; Chintiroglou et al.
This variation within and among species allows strong comparative tests relating cnida scaling to species habitats and tissue functions.
In a companion study, Francis (2004) shows how scaling analysis can be used to detect evolutionary changes in cnida size and shape by comparing homologous cnida populations from different anemone tissues and species.
We demonstrate for the first time that scaling studies using data on cnida size and anemone body size can be useful for distinguishing between closely related species, even when the size ranges for homologous cnida populations are overlapping.
We have coined the term "afferent mechanisms" of cnida discharge to refer to those processes acting to or toward the undischarged cnida to regulate or initiate discharge, and to distinguish them from mechanisms acting out of or from the discharged cnida's effector functions, which we have termed "efferent mechanisms" (Thorington and Hessinger, 1996).
t] with adhesive force probes in the absence of any cnida discharge.
We define mechanisms that regulate the initiation of cnida discharge (i.
As used in this report, the terms cnida adhesion, tentacle adherence, intrinsic adherence, and adhesive force have specific meanings associated with aspects of efferent mechanisms.