In sea urchin embryogenesis, the mouth is formed ____
a. where the archenteron contacts the ectoderm
b. by the blastopore
c. by the blastocoel
d. by migrating secondary mesenchyme cells
e. where the blastopore contacts the ectoderm
ANSWER: a
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Which of the following is a true statement about monocots and eudicots?
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