guard cell


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guard cell

n.
One of the paired epidermal cells that control the opening and closing of a stoma in plant tissue.

guard cell

n
(Botany) botany one of a pair of crescent-shaped cells that surround a pore (stoma) in the epidermis. Changes in the turgidity of the cells cause the opening and closing of the stoma

guard′ cell`


n.
either of a pair of crescent-shaped cells that flank each plant pore and control its opening and closing by means of turgidity.

guard cell

(gärd)
One of the paired cells that control the opening and closing of a stoma of a leaf. When swollen with water, guard cells pull apart from each other, opening the stoma to allow the escape of water vapor and the exchange of gases. When drier, guard cells move closer together, allowing the plant to conserve water. See more at cell.
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References in periodicals archive ?
Guard cells: At ventral surface no significant changes have been observed in guard cell lengths during winter months.
Designed to be useful to both industrial and academic researchers, the 14 papers here cover receptor kinases and their ligands, heterotrimeric G-protein-coupled signaling in higher plants, ROP/RAC GTPases, mitogen-activated protein kinase cascades, calcium signals (their regulation, paradigms and networks), reactive oxygen signaling, lipid-mediated signaling, plant actin-binding and microtubule-binding proteins, PCI complexes and the ubiquitin proteasome system in development, signaling between the organelles and the nucleus, signaling by protein phosphorylation in cell division, guard cell signaling and molecular networks of abiotic stress signaling.
The electrochemical cells were a postcolumn guard cell and analytical cell containing dual electrodes in series.
The main characteristics noted in this paper include the epidermal cell shape and arrangement, and the stoma and guard cell shape and arrangement.
Moreover NO has been identified as a mediator of guard cell ABA signalling.
After HPLC separation, detection of SAM and SAH was accomplished using a model 5200A Coulochem II electrochemical detector (ESA) equipped with a dual analytical cell (model 5010) and a guard cell (model 5020).
Zeiger and his co-workers now have isolated guard cell chloroplasts and report that they convert light into a cellular fuel, ATP, as do the functional chloroplasts elsewhere in the plants.
Miller-Rushing and colleagues found that stomatal density declined while guard cell length increased in oaks and hornbeams, although these changes were not dependent on the magnitude of changes in CO2 concentrations.
5 chloroplasts per guard cell are not known from nature, with a single exception.
A rare abnormality in some grasses can result in axial GMC division, so that the resulting two (non-functional) guard cells are proximal-distal to each other (Stebbins & Shah, 1960), suggesting that a stabilized mutation could be responsible for the evolution of short-cell pairs.
In addition, guard cells surround the stomata, which are the small holes on the undersides of leaves that allow carbon dioxide to enter and oxygen to be released.
These changes typically include guard cells closing on leaves to reduce water loss, cessation of plant growth to reduce water consumption and myriad other stress-relieving responses.