deuterostome
Americannoun
-
Embryology. a mouth that develops separately from the blastopore.
-
Taxonomy. any member of the phyla (Chordata, Hemichordata, Echinodermata, Chaetognatha) in which the anus appears first, developing at or near the blastopore, cleavage is radial and indeterminate, and the mesoderm and coelom form from outgrowths of the primitive gut.
-
Any of a major group of animals defined by its embryonic development, in which the first opening in the embryo becomes the anus. At this stage in their development, the later specialized function of any given embryonic cell has not yet been determined. Deuterostomes are one of the two groups of animals that have true body cavities (coeloms), and are believed to share a common ancestor. They include the echinoderms, chaetognaths, hemichordates, and chordates.
-
Compare protostome
Etymology
Origin of deuterostome
Compare meaning
How does deuterostome compare to similar and commonly confused words? Explore the most common comparisons:
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
But strangely, the new deuterostome fossils seem to have no anus, presumably using the mouth for evacuation.
From New York Times ● Jan. 30, 2017
By comparing them with diverse bilaterian genomes, we identify shared traits that were probably inherited from the last common deuterostome ancestor, and then explore evolutionary trajectories leading from this ancestor to hemichordates, echinoderms and chordates.
From Nature ● Nov. 17, 2015
Aspects of deuterostome phylogeny continue to be controversial, however, notably the position of the sessile pterobranchs among hemichordates, and the surprising association of Xenoturbella18 and acoelomorph flatworms with ambulacrarians19 proposed by some studies.
From Nature ● Nov. 17, 2015
As the deuterostome develops, the mesoderm pinches off and fuses, forming a second body cavity.
From Textbooks ● Jan. 1, 2015
The body plan of the deuterostome at this stage looks very similar to that of the protostome, but the blastopore becomes the anus, and the second opening becomes the mouth.
From Textbooks ● Jan. 1, 2015
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
