deuterostome

American  

[doo-ter-uh-stohm, dyoo-] / ˈdu tər əˌstoʊm, ˈdyu- /

noun

1. Embryology. a mouth that develops separately from the blastopore.

2. 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.

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deuterostome Scientific  

/ do̅o̅′tə-rō-stōm′ /

1. 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.

2. Compare protostome

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Etymology

Origin of deuterostome

First recorded in 1945–50; deutero- + -stome

Compare meaning

How does deuterostome compare to similar and commonly confused words? Explore the most common comparisons:

• protostome vs. deuterostome

Example Sentences

But strangely, the new deuterostome fossils seem to have no anus, presumably using the mouth for evacuation.

From New York Times • Jan. 30, 2017

Although we cannot rule out a deuterostome placement for Xenoturbella, our analyses generally do not support a grouping of acoels with deuterostomes19.

From Nature • Nov. 17, 2015

Green boxes around the names indicate genes with pan-metazoan/bilaterian ancestry and without accelerated sequence change in the deuterostome lineage.

From Nature • Nov. 17, 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

The word deuterostome comes from the Greek word meaning “mouth second,” indicating that the anus is the first to develop.

From Textbooks • Jan. 1, 2015