Question

The higher invertebrates are divided into two evolutionary lines, protostomes and deuterostomes. This division is based on which developmental feature?

Answer 1

I am not exactly sure what you are asking, but I think that what you are looking for is that in deuterostomes, the first opening developing during embryonic development becomes the anus, while in protostomes the first opening becomes the mouth.

Answer 2

A.wether the blastopore ultimately develops into a mouth or an anus

B. wether the embryonic cells undergo spiral or radial cleavage

C. wether the coelom forms by splitting the mesoderm or through the pocket of the gut.

Answer 3

i think the answer will be b..

Answer 4

its not b

Answer 5

a