They also illustrate the formation of the visceral clefts by an outgrowth from the alimentary tract without any corresponding ingrowth of the external epiblast.
In the second group the kidney changes are apparently due to the general arteriosclerosis which, affecting the kidney vessels, causes changes leading to atrophy and subsequent fibrous tissue ingrowth of scattered areas.
The rudiment of the central nervous system has the form of a solid keel-like ingrowth of ectoderm along the mid-dorsal line, which only secondarily becomes hollowed out--just as happens in Teleostean fishes.
A remarkable peculiarity of the Cyclostomes lies in the fact that the pituitary ingrowth of ectoderm does not, as in other forms, become involved in the inpushing of ectoderm which forms the buccal cavity.
It shows a pronounced epithelial ingrowth into the corium (Mettam).
An outgrowth of brain substance, on the other hand, forms the retina, while a third process is a lateral ingrowth of connective tissue, which afterwards changes into the vitreous humour of the eye.
The eye is formed by a simultaneous and corresponding ingrowth of one part and outgrowth of another.
In this order the axis is formed as an ingrowth of the ectoderm of the base of the mother zooid of the colony, the cavity of the ingrowth being filled by a horny substance secreted by the ectoderm.
The mucous lining is restored by ingrowth from the margins, and there is evidence that some of the secreting glands may be reproduced.
This granulation tissue is gradually replaced by young cicatricial tissue, and the surface is covered by the ingrowth of epithelium from the edges.
The effect is soon shown by the ingrowth of healthy epithelium from the surrounding skin, and at the same time the discharge is lessened.
At the posterior end of the hemisphere a small area of its wall remains thin and membranous, and this becomes pushed into the lateral ventricle by an ingrowth of blood-vessel to form the huge lateral plexus ( = plexus hemisphaerium).
This is indicated by the fact that they appear in some cases to be lined by an ingrowth of ectoderm.
The fins, both median and paired, obtain their musculature by the ingrowth into them of muscle buds from the adjoining myotomes.
The thyroid gland has a somewhat similar origin, it beginning as an ingrowth from the lower section of the pharynx and extending down to the lower part of the neck.
It begins to form early in the embryo life as an epithelial ingrowth from the throat, and extends from the neck into the chest.
A); at the tip of this is formed a thickening of the ectoderm, arising primitively as a hollow ingrowth (fig.
At a later period a mesoblasticingrowth with a blood-vessel makes its way in many forms into the cavity of the vitreous humour, accompanied by two folds in the walls of the free edges of the choroid fissure (fig.
The same ingrowthcauses the obliteration of the segmentation cavity.
The lens of the eye is formed as an ingrowth of the nervous layer only, and opposite the hind-brain the auditory sack (fig.
In Amphibia the alimentary cavity is formed coincidently with a true ingrowth of cells from the point where epiblast and hypoblast become continuous; and from this ingrowth the dorsal wall of the alimentary cavity is formed.
This ingrowth of the superior maxillary process is the rudiment of the hard palate.
The arrangement of the ingrowth through the choroid slit in Elasmobranchii (Scyllium) has been partially worked out, and so far as is at present known the agreement between the Avian and Elasmobranch type is fairly close.
In Triton there is no vascular ingrowth through the choroid fissure, but a few mesoblastic cells pass in which represent the vascular ingrowth of other types.
There is formed below it a floor of lower layer cells, derived partly from an ingrowth from the two sides, but mainly from the formation of cells around the nuclei of the yolk (fig.
According to Koelliker this ingrowth subsequently becomes split into two laminae, one of which forms the cornea, and the other the anterior part of the vascular sheath of the lens with its membrana pupillaris.
Firstly it is extremely doubtful whether the invagination of the secondary optic vesicle is to be viewed as an actual mechanical result of the ingrowth of the lens.
This ingrowth of the epidermic layer is shewn in fig.
Each ingrowth of the enamel organ forms an =enamel cap=, which gradually embraces the dental papilla, and at the same time appears to be pushed on one side, owing to the growth not being uniform.
The groove gradually becomes converted into a series of sockets by the ingrowth of transverse bars of bone.
One end of the blastopore becomes nearly closed, and an ingrowth of ectoderm takes place around it to form the stomodaeum or fore-gut and mouth.
The anal opening forms at a late period by a very short ingrowth or proctodaeum coinciding with the blind termination of the rectal peduncle (fig.
It is due to an arrest of development, whereby the closure of the primary medullary groove and the ingrowth of the mesoblast to form the spines and laminæ fail to take place.
The ingrowth of synovial membrane may fill up the cavity of the joint, or may divide it up into compartments.
The external layer of columnar cells has now vanished, and the gland is divided up by the ingrowth of connective-tissue septa into a number of areas or lobules--the rudiments of the future follicles.
In the gill-slits of Torpedo I have observed a very slight ingrowth of the external skin towards the hypoblastic outgrowth in one single case.
There is as little trace at this, as at the previous stages, of an ingrowth of epiblast, to form a median portion of the central nervous system.
It arises as a ciliated epiblastic ingrowth which meets the free end of the archenteric sack, fuses with it, and shortly afterwards opens into it (fig.
The growth of the water-vascular canals keeps pace with that of the arms, and the tube feet become supported at their base by an ingrowth of calcareous matter.
It is stated to be developed as an ingrowthof the epiblast.
The loss of juvenal hair is less readily observed than the ingrowth of new postjuvenal hair on account of the greater time required for the growth of any individual hair than for the sudden loss of a hair.
Not only is the juvenal pelage distinguishable from the postjuvenal pelage, but the sequence of ingrowth of postjuvenal pelage follows a regular pattern that is usually different from that of subsequent molts.
Every gland is formed by an ingrowth from an epithelial surface.
This ingrowth may from the beginning possess a tubular structure, but in other instances may start as a solid column of cells which subsequently becomes tubulated.
Contracted shell apertures occur also in Ammonitoidea, the condition reaching an extreme in Morphoceras, where the original aperture is subdivided by the ingrowth of the sides, so that only five small separate apertures remain.
B, Ingrowth of the ring-like wall so as to form a sac, the primitive optic vesicle of Loligo.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "ingrowth" in a variety of sentences. We hope that you will now be able to make sentences using this word.
