heterocyst


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heterocyst

(hĕt′ər-ə-sĭst′)
n.
A large, thick-walled, nitrogen-fixing cell that occurs at intervals along the filaments of certain cyanobacteria.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

heterocyst

a specialized CELL responsible for NITROGEN FIXATION in certain CYANOBACTERIA.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005
References in periodicals archive ?
Mostly cyanobacteria protect nitrogenase from damage by intracellular oxygen by carrying out nitrogen fixation in morphologically and physiologically differentiated cells called heterocysts whereas photosynthesis takes place simultaneously in spatially separated vegetative cells [14-17].
Golden, Cyanobacterial Heterocysts. Cold Spring Harbor Prospect.
Caption: Figure 3: Red triangle for large carcinoma lesions at the lower right corner; red arrow for small lesions composed of dozens of heterocyst reunion on the left side.
(b) Pathology section of thyroid isthmus: red triangle for large carcinoma lesions; red arrow for small lesions composed of dozens of heterocyst. (c) Pathology section of left thyroid lobe: red arrow for psammoma body.
Within an hour, these cells could be seen attached to heterocysts in the same manner as in the two-membered culture (Fig.
between nitrogen levels and heterocyst formation in Anabena spp.: Lac
Also, heterocyst abundance in Oyster Pond is low compared to lakes with high rates of N-fixation (6).
The nitrogen-fixing ability of each leaf of Azolla, because it is a function of the heterocyst frequency of the symbiont it houses (Watanabe, 1982), varies with leaf maturity.
Nitrogen fixation and heterocyst formation in cyanobacteria is inhibited by peptides (Yoon and Golden, 1998), whereas abdominal pumping (for larval release and dispersal) in mud crab is stimulated by small peptide cues (Forward et al., 1987).
Except for some groups, the diazotrophic (i.e., [N.sub.2]-fixing) cyanobacteria have specialized cells called heterocysts only where fixation of gaseous nitrogen is conducted under aerobic conditions.