Formation of Mouth and Anus
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 protosomes 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.
Read more about this topic: Deuterostome
Famous quotes containing the words formation of, formation and/or mouth:
“It is because the body is a machine that education is possible. Education is the formation of habits, a superinducing of an artificial organisation upon the natural organisation of the body.”
—Thomas Henry Huxley (1825–1895)
“Out of my discomforts, which were small enough, grew one thing for which I have all my life been grateful—the formation of fixed habits of work.”
—Elizabeth Stuart Phelps (1844–1911)
“May Allah keep her
And other wives from me. But this young slave
For the Caliph? Well, only her thin mouth to save
My soul I can’t forget, nor her slack eyes:
The oasis of age is sand and lies.”
—Allen Tate (1899–1979)