d, Lower cortical layer.
c, Cortical bundles.
The stereom is furnished either by cortical cells or by the tracheal elements, in a few cases by fibres which arc probably homologous with sievetubes.
E, epidermis; q, phellogen; 1, cells, and ~1, the pheliogen of the lenticel; k, cortical parenchyma, containing chlorophyll.
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 food so absorbed passes to the outer cortical mycellum, and from this tc the inner hyphae, which appear to be the organs of the interchangi of substance, for they are attracted to the neighborhood of thi nuclei of the cells, which they enter, and iii which they form agglom erations of interwoven filaments.
If a clean cut remains clean, the cambium and cortical tissues soon form callus over it, and in this callusregenerative tissuenew wood, &c., soon forms, and if the wound was a small one, no trace is visible after a few years.
The cortical tissues gradually shrink and dry up, turning brown and black in patches or all over, and when at length the cambium and medullary ray tissues dry up the whole twig dies off.
Latex, though chiefly secreted in vessels or small sacs which reside in the cortical tissue between the outer bark and the wood is also found in the leaves and sometimes in the roots or bulbs.
The cerebral cortex, and, more definitely, the cortical elements (nerve cells), formed the seat of the activity of the soul, and were ordered into departments according to various functions.
The exciting cause of the hypertrophy, in the case of the typical galls, appears to be a minute quantity of some irritating fluid, or virus, secreted by the female insect, and deposited with her egg in the puncture made by her ovipositor in the cortical or foliaceous parts of plants.
By the fusion of the hyphae in the middle of the mycelium a pseudo-parenchymatous cortical layer has begun to form.
The typical heteromerous thallus shows on section a peripheral, thin and therefore transparent, layer, the cortical layer, and centrally a mass of denser tissue the so-called medullary layer, between these two layers is the algal zone or gonidial layer (figs.
The term epithallus is sometimes applied to the superficial dense portion of the cortical layer and the term hypothallus to the layer, when specially modified, in immediate contact with the substratum; the hypothallus is usually dark or blackish.
The cortical layer is usually more developed on the side towards the light, while in many lichens this is the only side provided with a cortical layer.
The podetia of some species of Cladonia possess no cortical layer at all.
The surface of the thallus often exhibits outgrowths in the form of warts, hairs, &c. The medullary layer, which usually forms the main part of the thallus, is distinguished from the cortical layer by its looser consistence and the presence in it of numerous, large, air-containing spaces.
which carries with it r, Cortical layer.
a, Upper cortical layer.
If the cortical layer should exhibit positive reaction and the medulla of the same species a negative reaction with both reagents, the result is represented thus, K CaCI i.
An epidermis-like or cortical protective outer layer is very common, and is usually characterized by the close septation of the densely interwoven hyphae and the thickening and dark colour of their outer walls (sclerotia, Xylaria, &c.).
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.
Ziehen has noted exaltation of the jerk to follow extirpation of a cortical centre.
It will be noted from it that there is no direct relation between the extent of a cortical area and the mass of muscles which it controls.
The mass of muscles in the trunk is greater than in the leg, and in the leg is greater than in the arm, and in the arm is many times greater than in the face and head; yet for the last the cortical area is the most extensive of all, and for the first-named is the least extensive of all.
In the diagram there is indicated the situation of the cortical centres for movement of the vocal cords.
Heidenhain's view is that the cortical centres of the hemisphere are inhibited by peculiar conditions attaching to the initiatory sense stimuli.
Most of these cortical bundles are collateral in structure, but in some the xylem and phloem are concentrically arranged; the secondary origin of these bundles from procambium-strands was described by Mettenius in his classical paper of 1860.
A common phenomenon in cycads is the production of roots which grow upwards (apogeotropic), and appear as coralline branched structures above the level of the ground; some of the cortical cells of these roots are hypertrophied, and contain numerous filaments of blue-green Algae (Nostocaceae), which live as endoparasites in the cell-cavities.
A striking feature in the roots of several genera, excluding the Abietineae, is the occurrence of thick and somewhat irregular bands ofthickening on the cell-walls of the cortical layer next to the endodermis.
In the cortical tissue beneatJI each furrow a wide intercellular space is present running the length of the internode, and called the (C, D, E from Strasburger's Lehrbuch der Bolanik, by permission of Gustav Fischer.) FIG.
Lucid dreams do tend to occur in periods of higher cortical arousal.
The area of the cortical contusion is outlined in purple.
cortical dysplasia may result in refractory partial seizures.
cortical neurons varies across the body.
cortical reorganization in order to develop new strategies for visual rehabilitation.
Current and future studies will investigate neurovascular coupling over a broad range of stimulus parameters and cortical areas.
Chronic hypoxaemia appears to be a major cause of maldevelopment of the cortical neuron dendrites and axonal bed.
There were no significant differences in cortical volumetric bone mineral density (vBMD) at the radius or tibia diaphysis between the groups.
disarray in cortical dendrites and neurobehavioral failure II.
However, lucid dreams do tend to occur in periods of higher cortical arousal.
Focal cortical dysplasia may result in refractory partial seizures.
It may still be enough to cause long term damage or weakness in the cortical areas above in the central longitudinal fissure.
glutamate activated signaling pathways in cortical Peter Kind graduated from Dalhousie University with a B.S. in Neurosciences in 1988.
Our preliminary results indicate that cortical cells may be responding to temporal cues in flickering or moving gratings.
High incidence of cortical atrophy of the cerebral and cerebellar hemispheres in Cushing's disease.
Anarchic, hypercellular cortices with disruption of normal cortical lamination and radial alignment of neurones are the striking low-power features.
Cortical blindness does occur in about 4% of the cases of cerebral malaria.
maldevelopment of the cortical neuron dendrites and axonal bed.
The authors conclude that familial perisylvian polymicrogyria seems to be genetically heterogeneous, and is an as yet undescribed syndrome of cortical maldevelopment.
These features all indicate that DNT arises on a background of cortical malformation.
malformations of cortical development that appeared normal on conventional MRI.
If medical treatment fails a cortical mastoidectomy is performed.
neurobiology of the cortical dissociative processes has never been explored by scientific research.
The receptive field size of cortical neurons varies across the body.
Once the cortical cuts have been made a small osteotome is used to complete the graft removal.
The section shows from the pith (at right) to the cortical parenchyma (at left ).
We are interested in the nature, extent, and dynamics of cortical reorganization in order to develop new strategies for visual rehabilitation.
roc analysis was performed to assess the ability of the cortical width measurements to detect low systemic bone mineral density.
subcortical system, which is replaced by an experience-dependent cortical system.
tend to occur in periods of higher cortical arousal.
We are investigating both the structure and function of these cortical areas and their reciprocal connections with the auditory thalamus.
Brain imagining studies (MRI and fMRI) include development of an automated method to localize cortical tubers.
This in several cases runs vertically downwards for some distance in the outer cortex, and ends blindlythe lower end or the whole of the trace being band-shaped or star-shaped so as to present a large surface for the absorption of water from the adjacent cortical cells.
They arise usually in the gonidial layer of the thallus by division of the gonidia and the development around them of the hyphal investment; their increase in number leads to the rupture of the enclosing cortical layer and the soredia escape from the thallus as a powdery mass (fig.
The broad cortical region, which con tains many secretory canals, is traversed by numerous vascular bundles (fig.
The armour-plates are often exquisitely sculptured, and may be produced into spines or perpendicular plates to give greater surface extension, as we find in other plankton organisms. The cortical plasma may protrude pseudopodia in the longitudinal groove; it contains trichocysts in several species, true nematocysts in Polykrikos.
Normally, symptoms of fatigue would result from a reduction in cortical activation that would reduce the firing of putamen neurons.
ROC analysis was performed to assess the ability of the cortical width measurements to detect low systemic bone mineral density.
My main area of interest is the interaction between cortical and subcortical structures underlying human cognition, emotion and behavior.
Early face recognition abilities are thought to be served by a subcortical system, which is replaced by an experience-dependent cortical system.
Portuguese Water Dogs may also grow and be affected by Addison's disease, an adrenal cortical disease that can be treated.
When a person suffers from a cortical dementia, such as Creutzfeldt-Jakob disease or Alzheimer's disease, they typically have difficulty with language skills and memory.
Cortical dementia occurs as a result of a disorder that influences the cerebral cortex, the outer layers of the brain, where cognitive processes including language and memory take place.
While cortical dementia affects the outer layers of the brain, subcortical dementias are related to dysfunctional parts of the brain beneath the outer layers.
With these types of dementia, symptoms like the memory loss associated with cortical dementia are not exhibited.
These procedures allow for assessment of dominant (left-sided brain) functioning or higher cortical function.
Glucocorticoids-A general class of adrenal cortical hormones that are mainly active in protecting against stress and in protein and carbohydrate metabolism.
Dyslexia is a problem involving higher (cortical) processing of symbols in the brain.
Compact cortical bone, representing about 80 percent of the mature skeleton, supports the body, and features extra thickness at the midpoint in long bones to prevent the bones from bending.
This is because it contains an amino acid called L-theanine, which was shown in a 2006 Nagoya University Department of Psychology study to reduce physiological stress responses "via the inhibition of cortical neuron excitation."
con.) green assimilating cortical branches, which are the ends of branches from the medulla and fit tightly together, forming the continuous surface of the plant.
In all cases, while the internal threads which bear the cortical branches consist of elongated cells with few chromatophores, and no doubt serve mainly for conduction of food substances, the superficial cells of the branches themselves are packed with chromatophores and form the chief assimilating tissue of the plant.
In the bulky forms colorless branches frequently grow out from some of the cortical cells, and, pushing among the already-formed threads in a longitudinal direction, serve to strengthen the thallus by weaving its original threads together.
In the leafy shoot this function is mainly localized in the cortical tissue of the leaves, known as mesophyll, Mesophyli.
In some cases where there is apparently a well-marked plerome at the apex, this is really the young pith, the distinction between the stelar and cortical initials, if it exists, being, as is so often the case, impossible to make out.
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