File:Reptilia formation of hypoblast (entoderm) layer.jpg

From Wikimedia Commons, the free media repository
Jump to navigation Jump to search

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]

Public domain

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. Note that a few countries have copyright terms longer than 70 years: Mexico has 100 years, Jamaica has 95 years, Colombia has 80 years, and Guatemala and Samoa have 75 years. This image may not be in the public domain in these countries, which moreover do not implement the rule of the shorter term. Honduras has a general copyright term of 75 years, but it does implement the rule of the shorter term. Copyright may extend on works created by French who died for France in World War II (more information), Russians who served in the Eastern Front of World War II (known as the Great Patriotic War in Russia) and posthumously rehabilitated victims of Soviet repressions (more information).

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/TimeThumbnailDimensionsUserComment
current21:58, 11 March 2024Thumbnail for version as of 21:58, 11 March 2024961 × 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.

There are no pages that use this file.

Retrieved from "https://commons.wikimedia.org/w/index.php?title=File:Reptilia_formation_of_hypoblast_(entoderm)_layer.jpg&oldid=859706414"