periderm


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per·i·derm

, periderma (per'i-derm, -i-dĕr'mă),
The outermost layer of the epidermis of the embryo and fetus to the sixth month of intrauterine life; desquamated peridermal cells are a considerable component of the vernix caseosa.
Synonym(s): epitrichium
[peri- + G. derma, skin]

periderm

A transiently expressed superficial layer that surrounds the developing epidermis.

per·i·derm

, periderma (per'i-dĕrm, -dĕr'mă)
The outermost layer of the epidermis of the embryo and fetus up to the sixth month of intrauterine life; desquamated epitrichial cells are a considerable component of the vernix caseosa.
Synonym(s): epitrichium.
[peri- + G. derma, skin]

periderm

a protective tissue formed in roots and stems that has undergone SECONDARY THICKENING, consisting of an outer cork zone, an underlying phellogen (cork cambium) and with a phelloderm (secondary cortex) beneath that.
References in periodicals archive ?
Their findings showed that the fertile-zone morphological modifications correspond to several anatomical ones, especially in relation to the early development of periderm and loss of fibers in the secondary xylem and phloem.
Stem Epidermis 16.94 18.61 17.70 0.74 14.68 19.10 cell Pith cell 30.34 76.03 51.28 17.83 (diameter) Trachea 8.85 18.33 14.67 3.75 (diameter) Endodermis 6.81 13.04 10.67 2.78 18.74 39.37 cell Leaf Upper 8.78 26.01 18.01 7.37 24.16 42.42 epidermis cell Upper 18.38 20.31 19.05 0.79 21.79 34.53 stomata Trachea 4.66 11.24 7.03 2.08 (diameter) Lower 12.07 17.10 14.17 2.15 18.48 26.52 stomata Lower 7.73 14.22 11.62 2.97 26.23 16.94 epidermis cell Root Periderm 9.54 15.26 13.12 2.41 16.17 22.80 cell Trachea 13.84 34.75 22.01 7.71 (diameter) Avr.
After the first hour of incubation, Pb was found in the cell walls of periderm of the rhizomes of all the plants, wherein a small amount of the metal was also found in the outer layers of the cortex of the Filipendula ulmaria.
The healing process may also have influenced the disease severity because the cantaloupe produces lignin and suberin during tissue healing, depositing these compounds on the walls of injured cells to form a lesion periderm (JACOMINO et al., 2004), which may provide a structural resistance mechanism against infection.
Tegelaar EW, Hollman G, Vandervegt P, de Leeuw JW, Holloway PJ (1995) Chemical characterization of the periderm tissue of some angiosperm species: Recognition of an insoluble, nonhydrolyzable, aliphatic biomacromolecule (suberan).
Expression of resistance to two distinct diseases suggested a possible common mechanism expressed in the tuber periderm. It was postulated that this may confer enhanced resistance to other diverse tuber diseases including black scurf and tuber soft rot.
Buchanan, "Endophytic bacterial communities in the periderm of potato tubers and their potential to improve resistance to soil-borne plant pathogens," Plant Pathology, vol.
Peterson, "Casparian bands occur in the periderm of Pelargonium hortorum stem and root," Annals of Botany, vol.
In 2006, Casey identified in a mouse high levels of the Notch1 receptor activated during the differentiation process of cells of the lingual, palatal, maxillary and mandibular periderm, from E11.5 to E14.5.
Skin development begins at 36 days of gestational age, with the formation of an epidermis consisting only of a basal layer of cells and a superficial periderm Less than 8 months later--assuming normal development--the newborn emerges with soft, moist, resilient skin that provides an excellent barrier that adapts rapidly to the change from immersion in liquid to air and light exposure.