This consists typically of close-fitting layers of cells with completely suberized walls, intended to replace the epidermis as the external protective layer of the plant when the latter, incapable as it is of further growth after its original formation, is broken and cast off by the increase in thickness of the stem through the activity of the cambium.
The epidermis of a very large number of species bears hairs of various kinds.
in the epidermis itself (rarely), in any layer of the cortex, or in the pericycle.
- Stinging Hair of Urtica dioica, with a portion of the epidermis, and, to the right, a small bristle (X60).
Usually they are absent from the cells of the epidermis, though in some of the lower plants they are met with there also.
In favour of seeing in the lateral trunks and their branches a vascular system, is the contractility of the former, and the fact of the intrusion of the latter into the epidermis, matched among the Oligochaeta, where undoubted blood capillaries perforate the epidermis.
Many species of Thysanoptera are known to be habitually parthenogenetic. The eggs are laid on the food-plant, those females possessed of an ovipositor cutting through the epidermis and placing their eggs singly within the plant-tissues; a single female may take five or six weeks to deposit all her eggs.
In many forms its hyphae are particularly thick-walled, and may strikingly resemble the epidermis of a vascular plant.
These hollow roots terminate blindly in the dorsal epidermis of the collar, and place the nervous layer of the latter in direct connexion with the fibres of the nerve-tube.
The body wall consists of an epidermis which secretes a delicate cuticle and is only ciliated in Aeolosoma, and in that genus only on the under surface of the prostomium.
Beneath the epidermis is a longitudinal layer of muscle-fibres which are separated into four distinct groups by the dorsal, ventral and lateral areas; these are occupied by a continuation of the epidermic layer; in the lateral areas run two thin-walled tubes with clear contents, which unite in the anterior part of the body and open by a pore situated on the ventral surface usually about a quarter or a third of the body length from the anterior end.
Its most usual seat of origin in the stem is the external layer of the cortex immediately below the epidermis; in the root, the pericycle.
The disease spreads by the mycelium growing ever the epidermis of the plant.
Doing this she bursts the epidermis of the rootlet, and her body projects into the surrounding earth.
This surface layer in the typically subaerial shoot of the sporophyte in Pteridophytes and Phanerogams is known as the epidermis, though the name is restricted by some writers, on account of developmental differences, to the surface layer of the shoot of Angiosperms, and by others extended to the surface layer of the whole plant in both these groups.
(After de Bary.) In A several cells of the epidermis plants.
They are found one on each cephalic tentacle, and are simply minute open pits or depressions of the epidermis, the epidermic cells lining them being pigmented and connected with nerves (compare fig.
pression of epidermis, opening downwards.
Sometimes the epidermis is considerably more developed by tangential division of its cells, forming a many-layered water-tissue.
In Lanice conchilega the posterior series of nephridia are connected by a thick longitudinal duct, which seems to be seen in its most reduced form in Owenia, where a duct on each side runs in the epidermis, being in parts a groove, and receives one short tubular nephridium only and occupies only one segment.
In correspondence with its water-absorbing epidermis function it is not cuticularized, but remains usually thinof Root, walled; the absorbing surface is increased by its cell~
In such leaves, there are a well-marked cuticle, a thick epidermis, a thick hypodermis at least on the upper side of the leaf, well-developed palisade tissue, and a poorly developed system of air-spaces.
Special thickenings of the diffuse nervous layer of the epidermis occur in certain regions and along certain lines.
The other type is called endctropic. The fungal filaments either penetrate the epidermis of the root, or enter it from the stem and ramify in the interior.
A further fact must be considered in deciding this question, which is the discovery of ramifying coelomic tubes, approaching close to, but not entering, the epidermis in the Polychaete Arenicola.
Externally is a thin cuticle; this covers the epidermis, which consists of a syncytium with no cell limits.
Throughout the Angiosperms the epidermis of the shoot originates from separate initials, which never divide tangentially, so that the young shoot is covered by a single layer of dividing cells, the dermatogen.
In the leaf-blade this sometimes aopears as a layer of thickened subepidermal cells, tht hypoderm, often also as subepidermal bundles of sclerenchymatou~ fibres, or as similar bundles extending right across the leaf from mu epidermis to the other and thus acting as struts.
The epidermis contains numerous groups of sense cells; beneath the epidermis there is rarely (Kynotus) an extensive connective tissue dermis.
In the aquatic genera the epidermis comes to consist entirely of glandular cells, which are, however, arranged in a single layer.
Then come the glandular surface (C), which is formed of smooth polished epidermis with numerous glands that secrete the fluid contents of the pitcher, and finally the detentive surface (D), of which the cells are produced into long and strong bristles which point A FIG.
In relation to its characteristic function of protection, the epidermis, which, as above defined, consists of a single layer of cells has typically thickened and cuticularized outer walls.
In all green plants which have a special protective epidermis, the cortex of the shoot has to perform the primitive fundamental function of carbon assimilation.
The main assimilating tissue, on the other hand, is under the upper epidermis, where it is well illuminated, and consists of oblong cells densely packed with chloroplasts and with their long axes perpendicular to the surface (palisade tissue).
This tissue remains living and is usually formed quiti early, just below the epidermis, where it provides the first periphera support for a still growing stem or petiole.
The epidermis in the stair and the surface layer of the root soon becomes differentiated froit the underlying tissue.
The branches of the stem arise by multiplication of the cells 01 the epidermis and cortex at a given spot, giving rise to a protuber ance, at the end of which an apical meristem is established.
E, epidermis; q, phellogen; 1, cells, and ~1, the pheliogen of the lenticel; k, cortical parenchyma, containing chlorophyll.
The only way in which their turgidity is modified is by the entry of water into them from the contiguous cells of the general epidermis and its subsequent withdrawai through the same channel.
From the outer cortical myceliuni, again, branches pass through the epidermis and grow out in the soil, In stich cases the roots of the plants are usuall) found spreading in soils which contain a large amount of humus, or decaying vegetable matter.
The capillaries sometimes (in many leeches and Oligochaeta) extend into the epidermis itself.
The fungus mycelium grows between the cuticle and the epidermis, the former being ultimately ruptured by numerous short branches bearing spores (conidia) by means of which the disease is spread.
Salicyclic acid is not absorbed by the skin, but it rapidly kills the cells of the epidermis, without affecting the immediately subjacent cells of the dermis.
c/i, epidermis; st stoma; me,, mesophyil; pal, palisade; spa, spongy tissue; Isp, inteicellular space; wi., water tissue; x, xylem; p/i, phioem; Phil, phloeoterma; sri, scierenchyma.
The opening and closing of the stomata is the result of variation in the turgidity 01 their guard cells, which is immediately affected by the condition of turgidity of the cells of the epidermis contiguous to them.
Usually the epidermis is immediately followed by the circular layer of muscles, and this by the longitudinal coat.
The clitellum consists of a thickening of the epidermis, and is of two forms among the Oligochaeta.
In the earthworms, on the other hand, the epidermis becomes specialized into several layers of cells, all of which are glandular.
We have thus the replacement of a spermatheca, corresponding to those of the remaining families of Oligochaeta, and derived, as is believed, from the epidermis, by a structure performing the same function, but derived from the mesoblastic tissues, and with a cavity which is coelom.
The nervous system is embedded in the epidermis, and the pairs of ganglia are separated as in Serpula, &c.; each pair has a longish commissure between its two ganglia.
(as it appears) of the epidermis, and that it performs the function of a spermatheca is shown by its containing spermatozoa, or, in Stuhlmannia, a spermatophore.
The development of these organs, which in the Protonemertine are but grooves in the epidermis, not far removed from the similar cephalic slits of many Turbellaria, reaches its height in Drepanophorus.
- At the base of the epidermis (which is in general ciliated) there is over the entire surface of the body a layer of nervefibres, occurring immediately outside the basement-membrane which separates the epidermis from the subjacent musculature.
In one family, the Ptychoderidae, the medullary tube of the collar is connected at intermediate points with the epidermis by means of a variable number of unpaired outgrowths from its dorsal wall, generally containing an axial lumen derived from and in continuity with the central canal.
Both male and female gonads consist of more or less lobulated hollow sacs connected with the epidermis by short ducts.
h, Epidermic cell-layer; mes, mesoblastic connective tissue; n, nerves; II, III, IV, V, depressions of the epidermis in each of which a cuticular lens will be formed.
The female burrows in the epidermis much as the female trap-door spider burrows in turf in order to make a nest in which to rear her young.
One chief means employed by nature in accomplishing this object is the investment of those parts of the organism liable to be attacked with an armour-like covering of epidermis, periderm, bark, &c. The grape is proof against the inroads of the yeastplant so long as the husk is intact, but on the husk being injured the yeast-plant finds its way into the interior and sets up vinous fermentation of its sugar.
The root of the French vine is attacked by the Phylloxera, but that of the American vine, whose epidermis is thicker, is protected from it.
So long as the epidermis of animals remains sound, disease germs may come in contact with it almost with impunity, but immediately on its being fissured, or a larger wound made through it, the underlying parts, the blood and soft tissues, are attacked by them.
In a second type they are situated at the ends of tracheal strands and consist of groups of richly protoplasmic cells belonging to the epidermis (as in the leaves of many ferns), or to the subjacent tissue (the commonest type in flowering plants); in this last case the cells in question are known as epithem.
epiphytic plants and desert plants) have absorptive hairs or scales on the leaf epidermis through which rain and dew can be absorbed.
The surface layer of the root, sometimes included under tht term epidermis, is fundamentally different from the epidermis of the stem.
The simplest type consists simply of a single elongated cell projecting above the general level of the lairs, epidermis.
The epithem is penetrated by a network of fine intercellular spaces, which are normally filled with water and debouch on one or more intercellular cavities below the epidermis.
types of glands also exist, either in connection with the epidermis or not, such as nectaries, digestive glands, oil, resin and mucilage glands, &c. They serve the most various purposes in the life of the plant, but they are not of significance in relation to the primary vital activities, and cannot be dealt with in the limits of the present article.l The typical epidermis of the shoot of a land plant does not absorb water, but some plants living in situations where they cannot depend on a regular supply from the roots (e.g.
In other cases the root structure of the stele continues up to the cotyledonary node, though the hypocotyl is still to be distinguished from the primary root by the character of its epidermis.
The lenticels of the stem are usually formed beneath stomata, whose function they take up after the stomata have been ruptured and cast off with the rest of the epidermis.
The setae ar ° invariably formed each within an epidermic cell, and they are sheathed in involutions of the epidermis.
Among the Archiannelida, in Aeolosoma and some Polychaetes, the whole central nervous system remains imbedded in the epidermis.
Nervous system often imbedded in the epidermis.
segments are the apertures of the Nervous system rarely atria.C, Perichaeta: the spermathecal pores (Aeolosoma) in continuity are between segments 6 and 7, 7 with epidermis.
They are minute worms with coloured oil drops (green, olive green or orange) contained in the epidermis.
In Hirudo and the Gnathobdellidae there is only one system of cavities which consist of four principal longitudinal trunks, of which the two lateral are contractile, which communicate with a network ramifying everywhere, even among the cells of the epidermis.
The cells of tl ommatidium are a good deal larger than the neighbouring common cells of the epidermis.
g, Line separating lens from the lens-forming or corneagen cells of the epidermis.
The epidermis consists of pyriform cells, which send richly branched processes to the superficial cuticle.
The chief peculiarities that distinguish Trematodes from their free-living allies, the Turbellaria, are the development of adhering organs for attachment to the tissues of the host; the replacement of the primitively ciliated epidermis by a thick cuticular layer and deeply sunk cells to ensure protection against the solvent action of the host; and (in one large order) a prolonged and peculiar life-history.
The epidermis has lost its connected epithelial character and its cilia, and the isolated cells have become sunk inwards retaining their S t- FIG.
3) the terms by which these parts are designated: The skin does not form eyelids; but the epidermis passes over the eye, forming a transparent disk, concave like the glass of a watch, behind which the eye moves.
It is the first part which is cast off when the snake sheds its skin; this is done several times in the year, and the epidermis comes off in a single piece, being, from the mouth towards the tail, turned inside out during the process.
The cuticle is secreted by an epidermis in which no cell boundaries are to be seen; it sends out processes into the bristles.
Correlated with their life in dry situations, the bulk of the tissue is succulent, forming a water-store, which is protected from loss by evaporation by a thickly cuticularized epidermis covered with a waxy secretion which gives a glaucous appearance to the plant.
It readily dissolves the epidermis of the skin and many other kinds of animal tissue - hence the former application of the "sticks" in surgery.
The organs are developed as invaginations of the epidermis of the foot, and in the majority of the Protobranchia the orifice of invagination remains open throughout life; this is also the case in Mytilus including the common mussel.
modification of the epidermis - myelonic as opposed to epidermic. The structure of the reputed eyes of several of the above-named genera has not been carefully examined.
D.Ep, The dorsal epidermis.
V.Ep, Ventral epidermis.
In effect (6) it traces the Turbellaria to small two-layered organisms consisting of an outer ciliated epidermis and a central syncytial tissue.
A pair of eyes lie dorsally and behind them is a b closed circlet, often pulled out into various shapes, of modified epidermis, to which an olfactory function has been attributed.
The tegmentum is pierced by numerous vertical ramified canals which contain epithelial papillae of the epidermis.
Plasmopara, &c. In Cystopus (Albugo) the "conidia" are abstricted in basipetal chain-like series from the ends of hyphae which come to the surface in tufts and break through the epidermis as white pustules.
Transverse section through the epidermis of an infected plum.
e, Epidermis ruptured.
Every leaf originates as a simple cellular papilla (fig 1), which consists of a development from the cortical layers covered by epidermis; and as growth proceeds, the fibro-vascular bundles of the stem are continued outwards, and finally expand and terminate in the leaf.
The typical foliage leaf consists of several layers, and amongst vascular plants is distinguishable into an outer layer (epidermis) and a central tissue (parenchyma) with fibro-vascular bundles distributed through it.
The epidermis (fig.
The cells of the epidermis are very closely united laterally and contain no green colouring matter (chlorophyll) except in the pair of cells - guard-cells - which bound the stomata.
The outer wall, especially of the upper epidermis, has a tough outer layer or cuticle which renders it impervious to water.
The epidermis is continuous except where stomata or spaces bounded by specialized cells communicate with intercellular spaces in the interior of the leaf.
It is chiefly on the epidermis of the lower surface (fig.
The lower epidermis is often of a dull or and pale-green colour.
The upper epidermis is frequently smooth and shining, and sometimes becomes very hard and dense.
Many tropical plants present on the upper surface of their leaves several layers of compressed cells beneath the epidermis which serve for storage of water and are known as aqueous tissue.
Below the epidermis of the upper side of the leaf there are one or two layers of cells, elongated at right angles to the leaf surface (fig.
In leaves having a very firm texture, as those of Coniferae and Cycadaceae, the cells of the parenchyma immediately beneath the epidermis are very much thickened and elongated in a direction parallel to the surface of the leaf, so as to be fibre-like.
They have a layer of compact cells on their surface, but no true epidermis, and no stomata.
These are collected in water, scraped over the edge of a shell to free them from adhering cellular tissue and epidermis, and more than once washed in a running stream, followed by renewed scraping till the desired purity of fibre is attained.
The structure of the epidermis of the under side of the leaf, with its contorted cells, is represented (X 160) in fig.
- Epidermis of Tea-leaf (under side): X 160.
The body is composed of a large number of segments; the prostomium bears a pair of tentacles; the nervous system consists of a brain and longitudinal ventral nerve cords closely connected with the epidermis (without distinct ganglia), widely separated in Saccocirrus, closely approximated in Protodrilus, fused together in Polygordius; the coelom is well developed, the septa are distinct, and the dorsal and ventral longitudinal mesenteries are complete; the nephridia are simple, and open into the coelom.
When rubbed into the skin with such substances as alcohol or glycerine, which are absorbed, atropine is carried through the epidermis with them, and in this manner - or when simply applied to a raw surface - it paralyses the terminals of the pain-conducting sensory nerves.
It is based upon the fact that the histological differentiation of the epidermis of their root is that generally characteristic of Monocotyledons, whilst they have two cotyledons - the old view of the epiblast as a second cotyledon in Gramineae being adopted.
A,a,Female Heterodera schachtii Schmidt, breaking through the epidermis of a root; the head is still embedded in the parenchyma of the root.
Soon afterwards there is an accumulation under the epidermis of a serum derived from the dilated blood-vessels.
The seeds when placed in water for some time become coated with glutinous matter from the exudation of the mucilage in the external layer of the epidermis; and by boiling in sixteen parts of water they exude sufficient mucilage to form with the water a thick pasty decoction.
On the skin we have a thick epidermis through which microbes cannot pass, although if an entrance is obtained for them by a prick or cut they may readily grow in the tissues below and spread from them throughout the whole body.
In the same way, washing the skin with spirit would tend to harden the epidermis and thus prevent the entrance of microbes; and the application of an ointment to an abrasion would have a similar action.
The thickening of the epidermis in the hands and feet, which occurs from constant use, is nature's provision for meeting the extra wear to which these parts are subjected by much use; but pressure is apt to cause the defensive process to be carried too far, and to lead to corns, which give rise to much pain and annoyance.
In psoriasis the epidermis separates in flakes at various spots which have not been subjected to pressure, and to cure it ointment containing tar or other products of the dry distillation of wood is employed.
The germinating spores are not only able to pierce the leaves and stems of the potato plant, and so gain an entry to its interior through the epidermis, but they are also able to pierce the skin of the tuber, especially in young examples.
cell from the epidermis of root of Pea with " infection thread " (zoogloea) pushing its way through the cellwalls.
When terminal the awn has three fibro-vascular bundles, when dorsal only one; it is covered with stomate-bearing epidermis.
In the greater number of mammals the skin is more or less densely clothed with a peculiarly modified form of epidermis known as hair.
Other epidermic appendages are the horns of ruminants and rhinoceroses - the former being elongated, tapering, hollow caps of hardened epidermis of fibrous structure, fitting on and growing from conical projections of the frontal bones and always arranged in pairs, while the latter are of similar structure, but without any internal bony support, and situated in the middle line.
Callosities, or bare patches covered with hardened and thickened epidermis, are found on the buttocks of many apes, the breast of camels, the inner side of the limbs of Equidae, the grasping under-surface of the tail of prehensile-tailed monkeys, opossums; &c. The greater part of the skin of the onehorned Asiatic rhinoceros is immensely thickened and stiffened by an increase of the tissue of both the skin and epidermis, constituting the well-known jointed " armour-plated " hide of those animals.
where stomata of peculiar form occur in the epidermis, while subepidermal strands of sclerenchyma occupy the ridges.
The mature sporangium had a wall of a single layer of cells, which were larger towards the base, where they continued into the epidermis of the sporangiophore.
The pinnae, except in a few filmy forms, are thick; in Kaulfussia large pores derived from stomata occur in the epidermis.
Very usually (but not in the Onychophora = Peripatus) all the parapodia are plated with chitin secreted by the epidermis, and divided into a series of joints - giving the " arthropodous " or hinged character.
which are like those of Chaetopods in (After Goodrich.) structure - viz.vesicles with an intravesicular lens, whereas the eyes of all other Arthropods have essentially another structure, being " cups " of the epidermis, in which a knob-like or rod-like thickening of the cuticle is fitted as refractive medium.
The nerveend-cells, which lie below the lens, are part of the general epidermis.
Two or three layers of cells inside the epidermis constitute the tissue of the ovary, and overlie somewhat similar layers which form the coats of the seed.
The nervous system lies in the epidermis, externally to the basementmembrane.
The epidermis, placed immediately within the cuticle, is composed of a single row of cells.
Beneath the epidermis is a thin cutis, which is followed by the muscular layers (external circular and internal longitudinal).
In each a differentiation takes place in the layers beneath the epidermis, by which an outer layer of small-celled tissue surrounds an inner portion of large cells.
The cuticularized epidermis, especially, is often thus preserved, and may be removed by the use of appropriate reagents and examined microscopically.
Stomata of the same structure as in Equisetum have been detected in the epidermis.
Ctenis has been incorrectly placed among the ferns by some authors, on account of the occurrence of supposed sporangia on its pinnae; but there is reason to believe that these so-called sporangia are probably nothing more than prominent papillose cells of the epidermis.
m In all larval forms, in the Caudata, and in a few of the Ecaudata (Xenopus, for instance), the epidermis becomes modified in relation with the termination of sensory nerves, and gives rise to organs of the same nature as those of the lateral line of fishes.
In addition to diffuse pigment (mostly in the epidermis), the skin contains granular pigment stored up r' in cells, the chromatophores, restricted to the cutis, which are highly mobile and send out r2 branches which, by contraction and expansion, may rapidly alter the coloration, most batrachians being in this respect quite comparable to the famous chameleons.
Weak solutions applied locally saponify fats, soften the epidermis, and thus act as slight stimulants and cleansers of the skin.
On a mucous membrane or a delicate skin it exerts an irritant action, which occurs more quickly than on a thickened epidermis, such as the scalp, and according to the strength and period of application there may result redness, a blister, or an ulcer.
Grade 2: Partial thickness skin loss involving epidermis and/or dermis and/or dermis.
The skin consist of two main layers, an outer layer called the epidermis and an inner layer called the dermis and an inner layer called the dermis.
Leather The epidermis is supported on the ridged surface of the underlying dermis is supported on the ridged surface of the underlying dermis.
The skin (see Figure 1) is composed of two major layers of tissue; the outer epidermis, and the inner dermis, and the inner dermis.
The layers of skin There are two main layers of skin: epidermis dermis dermis.
epidermis of thick skin at lower power.
epidermis of the leaves.
Retinol plumps skin, thickens the epidermis, improves texture and blood circulation and repairs the signs of sun damage.
Large numbers of neutrophils and lymphocytes penetrate the epidermis and entered the infected surface region.
The skin with hair follicles, hairy skin, e.g. on the scalp, has a thin epidermis and many sebaceous glands.
How to use: Use twice a week to lift the skin and nourish the epidermis.
Grade 2 Partial thickness skin loss involving epidermis, dermis or both.
The skin (see Figure 1) is composed of two major layers of tissue; the outer epidermis, and the inner dermis.
Star shaped scales protect both the upper and the lower epidermis of the leaves.
The female mites are 0.3 mm long and feed within the human epidermis.
The laser passes through the upper epidermis leaving it undamaged.
Boundaries:: During pattern formation, many genes are expressed in a segmentally repeated manner in the embryonic epidermis.
The growing seedlings should be kept out of the full sun until the typical thick epidermis has appeared.
epidermis and/or dermis.
By " onion skin " does you mean onion epidermis or outer leaf of an onion bulb?
We are using a variety of different approaches to identify new markers of stem cells in human and mouse epidermis.
Some new characters based on the structure of the leaf epidermis are included.
Keratinocytes from the skin epidermis are functionally specialized to protect against the damaging effects of external agents, including ultraviolet (UV) light.
With small forceps, take the fragment of epidermis (with hairs) and pull it smoothly perpendicular to the stem.
This allows a narrow penetration peg to enter the leaf epidermis and colonize the tissue, later forming large bulbous infection hyphae.
During successive annual molts, the epidermis peels off with the old hair to reveal the bright new pelage underneath.
permeateooth and supple skin. *By permeating the outer layers of the epidermis.
thymine dimers in human epidermis and erythema suggests that DNA is the chromophore for erythema.
UVB lights stimulates the melanocytes (special cells which account for around 5% of the epidermis) to produce a pigment called melanin.
i.e., Lower epidermis, with st., stoma.
in the epidermal cells of the leaf of species of Vanilla (\Vakker), and in the epidermis of different parts of the flower of Funkia, Ornithogalum, &c. (Zimniermann), highly refractive bodies of globular form, elaioplasts, which consist of a granular protein ground-substance containing drops of oil.
The setae ar Ã‚° invariably formed each within an epidermic cell, and they are sheathed in involutions of the epidermis.
Salicyclic acid is not absorbed by the skin, but it rapidly kills the cells of the epidermis, without affecting the immediately subjacent cells of the dermis ("true skin").
In a common gall-nut that authority distinguished seven constituent portions: an epidermis; a subdermic cellular tissue; a spongy and a hard layer, composing 1 P. Cameron, Scottish Naturalist, ii.
- One of the most perfect of the many specimens discovered and prepared by Herr Bernard Hauff, and showing the extraordinary preservation of the epidermis of the ichthyosaur, which gives the complete contour of the body in silhouette, the outlines of the paddles, of the remarkably fish-like tail, into the lower lobe of which the vertebral column extends, and the great integumentary dorsal fin.
SCABIES, or Itch, a skin disease due to an animal parasite, the Sarcoptes scabei (see Mite), which burrows under the epidermis at any part of the body, but hardly ever in the face or scalp of adults; it usually begins at the clefts of the fingers, where its presence may be inferred from several scattered pimples, which will probably have been torn at their summits by the scratching of the patient, or have been otherwise converted into vesicles or pustules.
The parenchyma of the leaf is the cellular tissue enclosed within the epidermis and surrounding the vessels (fig.
The upper epidermis alone possesses only small intercellular spaces, except where stomata happen to be present (fig.
The palisade layers of the mesophyll contain the larger number of chlorophyll grains (or corpuscles) while the absorption of carbon dioxide is carried on chiefly through the lower epidermis which is generally much richer in stomata.
There is a double covering of the anther - the outer, or exothecium, resembles the epidermis,and often presents stomata and projections of different kinds (fig.
In light skinned people, the melanin is concentrated deep in the epidermis, particularly in the stratum basale layer.
The similarity of action spectra for thymine dimers in human epidermis and erythema suggests that DNA is the chromophore for erythema.
Similar life-threatening consequences occur when large areas of necrotic epidermis are shed in toxic epidermal necrolysis, in adults usually due to drugs.
Epidermis: The epidermis is the outer layer of skin that protects the body from the environment.
It contains nerves, hair follicles and supplies the epidermis with oils.
A small motor moves the needles up and down to penetrate and deposit ink in the superficial (epidermis) and middle (dermis) layers of the skin.
A mole (nevus) is a pigmented (colored) spot on the outer layer of the skin (epidermis).
Hair consists of the shaft and the root, which is anchored into a follicle beneath the epidermis.
Shaft-The portion of the hair that extends from the follicle and goes beyond the surface of the epidermis.
It can be caused by soaps, detergents, solvents, adhesives, fiberglass, and other substances that are able to directly injure the skin by breaking or removing the protective layers of the upper epidermis.
A first-degree burn causes redness and swelling in the outermost layers of skin (epidermis).
A second-degree burn involves redness, swelling and blistering, and the damage may extend beneath the epidermis to deeper layers of skin (dermis).
Lichenification is the medical term for a leather- or bark-like thickening of the outermost layer of skin cells (the epidermis) as a result of long-term scratching or rubbing of itching lesions.
Even conventional medicine has adopted this age-old concept of bringing healing to the sick via feeding the mucous membranes in the epidermis, in the respiratory track, in the digestive track and in the genitourinary system.
Therefore, with skin that is constantly renewing itself, you must make sure the artist can manipulate the epidermis to create the butterfly that you are hoping for.
In order to remove a tattoo, the ink inside your epidermis must be broken down or removed from the body.
Skin is made of three layers: Epidermis, Dermis, and Subcutaneous Tissue.
The epidermis protects the lower layers.
If the epidermis is torn or damaged, bacteria can enter the body through the skin.
While the primary cause of wrinkles is the aging of the epidermis (the skin's under-layer), sun, other weather conditions, and even the facial expressions you use can contribute to those wrinkles!
Dr. Leffell: Ultraviolet A waves from the sun penetrate beneath the epidermis into the dermis.
Epidermis: This is the outermost, visible layer.
New cells are produced in the top layer, or epidermis.
Additionally, the epidermis protects the body from infection and prevents excessive water loss.
Waste is removed and oxygen and nutrients are provided to the epidermis by the dermis.
As your skin ages the epidermis loses its ability to retain water resulting in fine lines and wrinkles.
It's made of the same types of cells and the same three layers: the protective top layer called the epidermis, the supple middle layer called the dermis, and a deeper layer of subcutaneous fat.
This can include any place your epidermis reaches, including the lips, ears, scalp, and hands.
Heat rash that seeps sweat into the deeper layers of the epidermis cause larger blisters and a painful red rash.
These layers are the epidermis, dermis and the subcutaneous fat layer.
The epidermis skin layer is the outer, exposed lining.
Exfoliate your epidermis occasionally to aid the body in its effort to shed dead skin cells.
Freckles are tan, brown, or black spots that appear on the upper surface, or epidermis, of the skin.
As the skin suffers abrasions or injuries, new skin cells are produced on the underside of the epidermis and are then pushed up to the surface.
The word usage examples above have been gathered from various sources to reflect current and historial usage. They do not represent the opinions of YourDictionary.com.