Side view of an ovum with a completely formed blastodermic disc.
Owing to its smaller specific gravity the part of the ovum with the cumulus always turns upwards, like the blastodermic pole of a fowl's egg.
At a stage slightly before the closure of the yolk-blastopore the mantle is formed as a slight prominence at the blastodermic pole of the egg, and even at this early stage is marked by the presence of chromatophores.
The three pairs of Nauplius appendages and upper lip become subsequently formed as outgrowths from the sides of the ventral blastodermic thickening.
The yelk is a granular albuminous fluid, contained in a granular membranous sac (the blastodermic membrane) which is covered by an investing membrane called the vitelline membrane or yelk-bag.
It is a minute spherical sac, filled with an albuminous fluid, lined with its blastodermic or germinal membrane, in which is seated the germinal vesicle or vesicle of Purkinje.
A series of changes next take place which result in the formation of what has been called the blastodermic vesicle.
Schaefer describes the blastodermic vesicle of the cat as being throughout in a bilaminar condition before the formation of a definite primitive streak or of the mesoblast.
The whole of the blastodermic vesicle, except the embryonic area, represents the yolk-sack, and the growth of the hypoblast and then of the mesoblast round its inner wall represents the corresponding growths in the Sauropsida.
The blastodermic vesicle during the early stages of development lies freely in the uterus; and no non-vascular villi, similar to those of the Dog or the Rabbit, are formed before the appearance of the allantois.
A fold of the uterine wall appears to grow round the blastodermic vesicle, and to form a complete capsule for it, but the exact mode of formation of this capsule is a matter of inference and not of observation.
The blastodermicvesicle of the Guinea-pig becomes completely enveloped in a capsule of the uterine wall (decidua reflexa) (fig.
Although by this stage, which occurs in the rabbit between seventy and ninety hours after impregnation, the blastodermic vesicle has by no means attained its greatest dimensions, it has nevertheless grown from about 0.
The blastodermic vesicle is therefore formed of three areas, (1) the embryonic area with three layers: this area is placed where the blastopore was originally situated.
Curves of blastodermic layers and division of mesoderm in amniote embryo.
Embryo of bird, at beginning of third day, with four blastodermic layers, resulting from the division of the mesoderm into parietal and visceral layers, separated by the coelom cavity.
The egg is now called the blastula, blastosphere or blastodermic vesicle and the cellular membrane enclosing the segmentation-cavity forms the germinal membrane or blastoderm (Figs.
Oval embryonic area of rabbit's egg, detached with part of wall of blastodermic vesicle.
We have seen that the intestinal tube of all vertebrates is the product of two of the embryonal blastodermic layers, the entoderm and mesoderm.
While the blastula is being folded into a cup at the vegetal pole of its axis, the difference in the size of the blastodermic cells increases (Figure 1.
The former (blastodermic vesicle) is cenogenetic, and follows gastrulation.
The blastosphere may grow and expand by the blastodermiccells (at the surface of the sphere) dividing and increasing, and more fluid is secreted in the internal cavity.
In this way each blastodermic cell becomes a ciliated cell.
This new membrane, formed within the sac which originally enclosed the yolk of the ovum, now divides or separates itself into two distinct layers, known as the outer and inner blastodermic membranes, also called epiblast and hypoblast.
The outer one of the three is the primitive yolk sac, the second is the outer layer of the blastodermic membrane, and the third the inner layer, while the interior cavity of the egg is filled by the transparent fluid previously mentioned.
Between these two blastodermic membranes other minute tissues are formed, the office and end of which are not so fully understood, and the consideration of which would lead us into intricacies beyond our present purpose.
The first visible sign of the organic structure of the human form is discovered as it takes shape upon the exterior wall of the blastodermic membrane, known as the embryonic spot, and known also as the primitive trace or furrow.
Indeed, it may be said that these two blastodermic membranes are the body of the embryo which is to develop into the fully-formed physical man.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "blastodermic" in a variety of sentences. We hope that you will now be able to make sentences using this word.
