Deuterostomes

Jim Taylor
[subject]
Saturday, March 10, 2018, 09:27 (279 days ago)

Laughing out loud.

SPB
[subject]
Saturday, March 10, 2018, 09:33 (279 days ago) @ Jim Taylor

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Met more than a few underdeveloped ones

Russell Cottle
[subject]
Saturday, March 10, 2018, 09:38 (279 days ago) @ Jim Taylor

- No text -

Further definition & clarification

ORG
[subject]
Saturday, March 10, 2018, 10:15 (278 days ago) @ Jim Taylor

"The defining characteristic of the deuterostome is the fact that the blastopore (the opening at the bottom of the forming gastrula) becomes the anus, whereas in protostomes the blastopore becomes the mouth. The deuterostome mouth develops at the opposite end of the embryo from the blastopore and a digestive tract develops in the middle, connecting the two."

"In many animals these early development stages later evolved in ways that no longer reflect these original patterns. For instance, humans have already formed a gut tube at the time of formation of the mouth and anus. Then the mouth is formed first, during the fourth week of development, and the anus is created four weeks later, temporarily forming a cloaca."

So actually, there was a point when you were all mouth, and it's similarly likely that some never develop beyond this stage . . . visit social media for proof.

:-) :-) :-)

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