File:Reptilia formation of hypoblast (entoderm) layer.jpg
Jump to navigation
Jump to search
Size of this preview: 523 × 599 pixels. Other resolutions: 209 × 240 pixels | 419 × 480 pixels | 961 × 1,101 pixels.
Original file (961 × 1,101 pixels, file size: 1.03 MB, MIME type: image/jpeg)
Captions
Captions
Add a one-line explanation of what this file represents
Summary
[edit]| Description | Fig. 174. Formation of hypoblast (entoderm) layer in certain reptiles; major presumptive organ-forming areas of reptilian blastoderm. (A) Section through blastoderm of the turtle, Clemmys leprosa. This section passes through the primitive plate in the region where the entoderm cells are rapidly budded off (invaginated?) from the surface layer. It presumably passes through (E) in the area marked entoblast. It is difficult to determine whether the entoderm cells are actually invaginated, according to the view of Pasteels, or whether this area represents a region where cells are delaminated or budded off in a rapid fashion frorh the overlying cells. (B) Similar to (A), diagrammatized to show hypoblast cells in black. (C) Section through early blastoderm of the gecko, Platydactylus (=Rhacodactylus). Epiblast cells are shown above, primitive entoderm cells below. (D) A later stage showing primitive plate area with the appearance of a delamination or proliferation of entoderm (hypoblast) cells from the upper layer of cells. (E) Presumptive, organ-forming areas of the turtle, Clemmys leprosa, before gastrulation. (F) Presumptive, organ-forming areas of the epiblast of turtle and other reptiles if the hypoblast is budded off or separated from the underside of the epiblast without invagination. It is to be observed that B and D represent modifications by the author. |
| Date | |
| Source | https://archive.org/details/comparativeembry00nels/page/361/mode/1up?view=theater&q=BLASTULATION+ Comparative embryology of the vertebrates; with 2057 drawings and photos. grouped as 380 illustrations. |
| Author | Nelsen, Olin E. |
Licensing
[edit]
|
This work is in the public domain in its country of origin and other countries and areas where the copyright term is the author's life plus 70 years or fewer.  You must also include a United States public domain tag to indicate why this work is in the public domain in the United States.
|
| This file has been identified as being free of known restrictions under copyright law, including all related and neighboring rights. | |
|
This file, which was originally posted to an external website, has not yet been reviewed by an administrator or reviewer to confirm that the above license is valid. See Category:License review needed for further instructions.
|
File history
Click on a date/time to view the file as it appeared at that time.
| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 21:58, 11 March 2024 | 961 × 1,101 (1.03 MB) | Rasbak (talk | contribs) | {{Information |description=Fig. 174. Formation of hypoblast (entoderm) layer in certain reptiles; major presumptive organ-forming areas of reptilian blastoderm. (A) Section through blastoderm of the turtle, Clemmys leprosa. This section passes through the primitive plate in the region where the entoderm cells are rapidly budded off (invaginated?) from the surface layer. It presumably passes through (E) in the area marked entoblast. It is difficult to determine whether the entoderm cells are a... |
You cannot overwrite this file.
File usage on Commons
There are no pages that use this file.