Hypodermis


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hypodermis

[‚hī·pə′dər·mis]
(botany)
The outermost cell layer of the cortex of plants. Also known as exodermis.
(invertebrate zoology)
The layer of cells that underlies and secretes the cuticle in arthropods and some other invertebrates.

Hypodermis

 

in invertebrates (for example, crustaceans, arachnids, and insects), the thin layer of usually cylindrical epithelium lying immediately under the cuticle (which is formed by the secretory activity of the cells of the hypodermis). The various cutaneous glands and the tactile and olfactory hairs are located in the hypodermis. In nematodes, gastrotrichs, and several other worms, the hypodermis is a syncytium that secretes the cuticle.

In plants, the hypodermis is one or more layers of cells located under the epidermis of the stems, leaves, seeds, and fruits, or under the epiblem (piliferous layer) of the roots. The hypodermis is part of the primary cortex of stems, often consisting of cells with thickened walls, and may be classified by function as mechanical tissue. It is most characteristic of succulents. In leaves the hypodermis consists of one, or more often several, layers of cells of aquiferous tissue (for example, in a number of tropical plants) or of mechanical tissue (for example, in pines and sago palms). In the leaf the hypodermis is formed when the cells of the epidermis are divided by septa that are parallel to the surface of the leaf, such as in Ficus and Begonia, or from cells of the mesophyll of the leaf tissue lying under the epidermis, such as in some palms. In roots the outer layers of cells of the primary cortex are sometimes called the exodermis.

References in periodicals archive ?
Hypodermis (H)###0516-2###Four upper layers were collapsed into a hyaline, each layer only containing one or two layers of###Fig.
In the leaves cross sections of plants from treatments without calcium silicate silicon deposits were not observed in the bulliform cells, in the chlorenchyma or in the anticlinal walls of the epidermis and hypodermis.
The hypodermis in the claw is situated between the dermis and the pedal bone except in areas where it is absent, the dermis is directly joins to the bone.
These include: non-vascular fibrous strands located under the adaxial hypodermis and in the spongy parenchyma between the major vascular bundles, variable in shape and in number of fibers; round stegmata surrounding fiber strands; cellulose non-vascular fiber very elongated, acute at the ends, with thick walls; lignified vascular fibers short, septate, spindle-shaped and acute, located at the ends of the major and minor vascular bundles.
3), the skin consist of three layers: epidermis, dermis and hypodermis.
The layers above and below the dermis are the epidermis and hypodermis respectively.
Sleumer, druses were also observed on the hypodermis (Hermann & Perez Cuadra 2011).
Morphologically, the blemishes are collapsed hypodermis tissues related to shrunken or destroyed oil glands.
Cellulite develops in the most superficial of these layers, known as the hypodermis or subcutaneous fat layer.
The skin of this species consisted of three components: the epidermis, the dermis and hypodermis, with an average thickness of 308 um.
Chapters cover prenatal development of the integument, development and function of the epidermis, the dermis, and the hypodermis, and structure and function of the adult integument, as well as the role of blubber, thermoregulatory aspects of the skin, skin and buoyancy, and skin diseases and the natural environment.